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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Yoked Flows for Direct Representafi on of Scienfi fic Research</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Robert B. Allen</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>New York</string-name>
        </contrib>
      </contrib-group>
      <fpage>12</fpage>
      <lpage>21</lpage>
      <abstract>
        <p>We propose developing highly structured and interlocking, or yoked, descriptions for all aspects of scientific research reports. These structured descriptions would be based on rich standardized vocabularies. We use two principal sets of flows to provide such structured descriptions: (a) Research Design and Procedures; and (b) Hypotheses and Outcomes. The structured descriptions may also include the research question, threats to validity, and implications. We propose that the best way to capture and describe the structure of scientific research is by considering multiple flows which are yoked. The claims from the research are propositions and they can be coordinated in a knowledgebase. As an example, we examine Pasteur's study of germ theory and support interaction with the structured description of the study with a prototype graphical user interface. We also consider template structures for different parts of the research reports. Ultimately, structured research reports could be interwoven into structured and evolving digital-library knowledgebases.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Highly Structured Digital Library</kwd>
        <kwd>Microworld</kwd>
        <kwd>Research Designs</kwd>
        <kwd>Simulation Space</kwd>
        <kwd>Specific Comparisons</kwd>
        <kwd>Transitional Propositions</kwd>
        <kwd>Validity</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>We have been exploring direct representation for
scientific research reports. Direct representation
proposes that entire research reports can and
should be highly structured. Moreover, we
propose that collections of research reports can be
interwoven into a rich semantic knowledgebase.</p>
    </sec>
    <sec id="sec-2">
      <title>Semantic Models</title>
      <p>Causal models, whether explicit or implicit, are
central to science. Scientific research articles
would benefit from using highly structured models
which support state changes and causal relations.
We use “flows” as a generic term for sequences of
transitions such as workflows. flowcharts, plans,
mechanisms, and other causal sequences.
Potentially, flows could be circular or have
feedback loops.</p>
      <p>Recently, we have focused on the comprehensive
ontology SUMO [24] as the vocabulary for such
models. One important feature of SUMO that
distinguishes it from most other ontologies is the
inclusion of rules. We also propose the adoption
of object-oriented modeling [7] in place of
traditional approaches to presenting and
processing knowledgebases. We implement
transitions between object states and apply
linguistic models of “case roles” to describe them
[9].</p>
      <p>In previous work, we have proposed a broad
framework for flows that can be applied across
domains [6, 10]. We have conducted several
studies describing mechanisms and systems with
structured, semantic vocabularies. Building on the
modeling techniques in [9], we describe steps
toward developing a rich model-oriented
knowledgebase to support science. We describe
policies for making these simulations plausible and
useful. While our current work focuses on
qualitative models, the approach should also
support quantitative models.</p>
    </sec>
    <sec id="sec-3">
      <title>1.2 Scientific Research Reports</title>
      <p>There is a long tradition of research on scholarly
publications (e.g., [1, 30, 32]). Structure has
increasingly been added to descriptions of
scientific research. Taken to the logical
conclusion, we propose that research reports
should be totally structured. Structured research
reports have many advantages. For instance, they
can support interactive interfaces for visualizing
and exploring the relationships among interlocking
flows. Visualization of flows is related to timeline
visualizations (e.g., [2]).</p>
      <p>Several types of flows are already widely used in
science. Workflows are used to specify
experimental procedures (e.g., [14]). Mechanisms
are often central for describing complex
phenomena [6, 11]. However, before our work,
Research Designs (e.g., [28]) as distinct from
Research Procedures have not been explored as
structured flows.</p>
      <p>Beyond describing aspects of workflows and
research phenomena directly, other parts of science
research reports make claims and generalizations
about phenomena. These can be characterized as a
type of discourse [1, 2, 13, 15, 19, 25, 30]. We
agree with [21] that research inferences cannot be
based simply on formal logic. Rather, they follow
a preponderance of evidence and consistency with
other results.</p>
    </sec>
    <sec id="sec-4">
      <title>1.3 Pasteur’s Germ Theory</title>
      <p>Germ theory was a paradigm shift in biology. It
was sparked by the development of the microscope
and the resulting ability to see microbes. Louis
Pasteur was a major proponent of germ theory,
which was the notion that tiny organisms, invisible
1 While Pasteur’s report was not as detailed as current research
reports, it is straightforward and useful as an exemplar.
without the aid of a microscope, produced spoilage,
fermentation, and some diseases.</p>
      <p>One early controversy was whether microbes
developed only from other microbes or whether
they developed spontaneously. That is, whether
existing organisms are needed to propagate new
organisms and those existing organisms are carried
by air currents. We focus on a version of Pasteur’s
classic experiments that explored spontaneous
generation [23, 26]. Pasteur’s experiments are
generally regarded as pivotal in confirming the
importance of microbes and how they propagate.1</p>
    </sec>
    <sec id="sec-5">
      <title>1.4 Roadmap</title>
      <p>In [3], we used Pasteur’s germ theory experiments
to illustrate the potential for applying direct
representation to scientific research reports. In this
paper, we return to that example and describe how
several techniques proposed in our recent work can
be implemented to produce unified scientific
research reports.</p>
      <p>Our primary goal is the development of the
underlying modeling framework for the
organization and application of scientific
knowledge. These models emphasize causal
relationships (rather than classification) so we
focus on what might be called transitional
propositions. We also describe an interface for
interacting with the models.2
In short, we propose that the best way to capture
and describe the structure of scientific research is
by considering multiple flows which are yoked.
The claims from the research are propositions that
can be coordinated in a knowledgebase.
2 At this point, we are not focused on inference or text mining.
2.1</p>
    </sec>
    <sec id="sec-6">
      <title>STRUCTURED RESEARCH</title>
    </sec>
    <sec id="sec-7">
      <title>REPORTS</title>
    </sec>
    <sec id="sec-8">
      <title>Models and Knowledge</title>
    </sec>
    <sec id="sec-9">
      <title>Structures</title>
      <p>While science uses systematic manipulations
and/or observations, it also crucially depends on
models about the phenomena under investigation.
We employ two major flows to capture these two
aspects. The first describes the Research Design
and Procedure while the second describes the
Hypothesis (i.e., what might happen) and
Outcomes (i.e., what did happen).</p>
      <p>Research microworlds are where the
manipulations come together with the
phenomenon under investigation. States and state
changes are useful (at least implicitly) for models
that describe dynamic environments. Some states
are based on the properties of objects. Other states
are based on the relationship among objects (e.g.,
an object is “trapped”). Sealing a flask is a
complex action that achieves a state of separation.
Breaking the flask is a way to unseal it and
instantiate a new state in which the external air can
move into the flask. Many research activities are
workflows that involve multiple steps and
interlock with other flows [9, 10].</p>
      <p>While much of science is concerned with
developing general principles, sciences such as
geology and astronomy, as well as clinical
medicine, deal more with particulars. Reasoned
models can be developed for either general
(abstract) principles or instances.</p>
    </sec>
    <sec id="sec-10">
      <title>2.2 Creating a Research Space</title>
      <p>Traditional research papers follow the IMRD
(Introduction, Methods, Results, Discussion)3 [32]
framework. Swales [32] described the purpose of
the Introduction of a research report as “creating a
research space” (CARS). This includes defining a
3 Some publications do not use the exact IMRD structure but
usually follow some permutation of it.
3
Research Question, Research Motivation, and
Hypotheses.</p>
      <p>Addressing the Research Question is the
immediate goal of the research. Typically, it
involves determining the existence, properties,
mechanisms, processes, or applications associated
with an entity or phenomenon. In some cases, the
goal may simply be the replication of other
research or addressing some criticisms that were
raised about prior work. In this paper, we require
that Research Questions can be answered with
structured propositions.4
Examples of the Research Motivation might be
practical (e.g., to find cures for a disease) or simply
to acquire knowledge. Either way, it is an axiom,
a given representing a valuation. Additional
statements may link the Research Question to the
Research Motivation.</p>
      <p>The researcher then establishes plausible
hypotheses by considering the factors potentially
relevant to the Research Question by referring to
established principles and previous research.</p>
    </sec>
    <sec id="sec-11">
      <title>2.3 Research Design and Procedures</title>
      <p>Based on the hypotheses, a Strategy is determined.
The Strategy consists of the Research Design and
Research Procedure. The Design is an overall
framework for obtaining valid results.
Independent and dependent variables are key parts
of the Design. Typically, one of the hypotheses
proposes some causal relationship between the
independent and dependent variables. The
independent variable may be manipulated either
directly or indirectly. In natural experiments, the
researcher identifies a natural event that creates
conditions suitable for the research. These may
include cases from natural science, social science
[8], and medical science (e.g., the effects of
smoking on cancer). In field and laboratory
experiments, the researcher takes specific actions
to manipulate the test environment.</p>
      <p>Standard Research Designs are so entrenched in
some fields that many researchers are unaware of
4 See https://plato.stanford.edu/entries/questions/
them. In other fields, a variety of research
paradigms is used and their merits are debated.
[28] is a well-known analysis of the issues with
different research designs. It discusses a wide
range of designs and provides a notation for
describing them. Moreover, it compares the
possible threats to valid inference using different
research designs. While [28] is primarily based on
field research with randomization such as is
common in social science, it can and should be
applied more generally.</p>
      <p>It is highly desirable to have at least two conditions
for comparison [28]. This is especially true when
one group is a control group and there is
randomization of participants across conditions.
However, these recommendations are not followed
when a second group is difficult or impossible to
implement, or when the researcher believes that
he/she knows about and has controlled for possible
extraneous factors.</p>
      <p>The Research Procedure is a script or plan for the
researcher’s actions. It applies methods and
materials. Those are usually specific to the domain
under investigation and may threaten the internal
validity of the research if applied incorrectly.
2.4</p>
    </sec>
    <sec id="sec-12">
      <title>Hypotheses and Microworlds</title>
      <p>There is considerable controversy about the role of
hypotheses in scientific research. In cases such as
Pasteur’s experiment discussed below, the
hypotheses are sharply drawn and are associated
with a distinct, although not necessarily fully
understood, mechanism. However, in other cases,
a hypothesis may be nothing more than a hunch.5
Our models are typically situated in a microworld6
which is a spatial region that provides the context
for the interaction of objects involved in the
phenomenon under investigation [12]. The
5 Perhaps it would be better to use the term “potential
explanation” rather than hypothesis. For example, in [4] we
examined [33], a modern biology paper dealing with the
protein pathway related to Wallerian Degeneration. That paper
cast a wide net and tested hypotheses which seemed unlikely
to be relevant.
manipulations directly or indirectly change the
state of the microworld and/or its contents. In
other work (e.g., [7, 8, 10]) we allow complex
microworlds; potentially, they could be subdivided
and have different levels of temporal and spatial
granularity.
2.5</p>
    </sec>
    <sec id="sec-13">
      <title>Outcomes, Internal Validity, and</title>
    </sec>
    <sec id="sec-14">
      <title>Comparisons</title>
      <p>As the research is conducted, the raw data can be
structured and stored according to the semantic
model. The data can be manipulated and
workflows for data transformations and statistical
analyses can be included7 along with the massaged
data.</p>
      <p>Using the data, we can make comparisons across
the flows. These comparisons are the basis for
claims. Claims are propositions. They have a truth
value that expresses a judgment or opinion about
some aspect of the research (e.g., the causal
relationship between the independent and
dependent variables).</p>
      <p>The primary comparison is set up by the Research
Design. In Pasteur’s study which we analyze
below, the comparison is relatively simple. In
other cases (e.g., [33]), the comparisons may
involve complex objects and processes, and
statistical tests that require additional flows.
Research must satisfy many constraints; many
things can go wrong and invalidate the results.
[28] identifies two major types of validity for
research, internal and external validity8. Internal
validity refers to problems with the Research
Procedure and Methods, and whether they
implemented the intended research conditions.
The researcher may check on the effect of a novel
6 This term is adopted from object-oriented programming. In
our applications, it may be more appropriate to call it a
simulation space.
7 These could follow the scripts of any of several statistical
analysis packages, although a common interchange
framework would be preferred.
8 They also mention statistical conclusion validity and
construct validity.
or tricky manipulation. Such checks on the
manipulation would also be described with flows.
[28] lists potential threats to validity for each
research design. Structured research reports
should include specific structures for handling
each of these issues. For instance, the outcome
summary could have a list of hypotheses and
challenges to their validity.</p>
    </sec>
    <sec id="sec-15">
      <title>2.6 External Validity,</title>
    </sec>
    <sec id="sec-16">
      <title>Generalizations, and</title>
    </sec>
    <sec id="sec-17">
      <title>Explanations</title>
      <p>External validity refers to the ability to generalize
beyond the experiment. Some generalizations may
be straightforward, but others would be based on
conditions. [28] describes criteria for
generalizations. Generalization may require
referring to broader issues within the research area
or in other areas.</p>
      <p>We would like to model those broader contexts,
but, in many cases, they are not currently part of
any structured model base. Eventually, such a
model base could be developed; until then we can
sketch a temporary framework (see Section 3.4).
Explanations may simply state a general rule.
They may also try to describe how the rule applies
to a given situation. If pressed, a mechanism to
support the rule might be given. For instance, if
we were explaining why hot air balloons rise, we
would assert the rule that “hot air rises” and then
might go into a discussion of the molecular
dynamics of gasses (see Section 4.1).
3</p>
    </sec>
    <sec id="sec-18">
      <title>PASTEUR’S SPONTANEOUS</title>
    </sec>
    <sec id="sec-19">
      <title>GENERATION EXPERIMENT 3.1</title>
    </sec>
    <sec id="sec-20">
      <title>Overview</title>
      <p>Farmers have considerable interest in
understanding and controlling fermentation. The
results of Pasteur’s studies [23, 26, 31] are of
practical importance for endeavors such as dairy,
9 No systematic randomization was done and there was no
statistically significant sample, but the control groups suggest
5
wine, beer, tofu, and soy sauce making, and for
controlling infectious disease. In [3], we used
Pasteur’s research to explore the possibilities for
highly structured research reports. In this paper,
we take another step toward realizing that goal.
We consider one of a series of related experiments
by Pasteur. Specifically, we develop flows and an
interface for presenting a structured description of
one of Pasteur’s germ theory experiments.
Pasteur put a nutrient broth in two sets of flasks.
He boiled the broth and then sealed the neck of the
flasks. He observed the flasks and eventually
broke the neck open on one set of them. The flasks
that remained sealed did not show microbe growth,
while the flasks with the broken necks did.
We separate two main streams of activity in
describing the experiments. The first is the
Researcher Activity Model, which is what the
researcher does based on the Design and Procedure.
The second is the Outcomes Model, which is what
happens, or could happen, in the environment
under investigation. Although we distinguish them,
the two streams are closely interlinked or yoked.
We focus on modeling the microworld and frame
the experiment as a research design with two
conditions. In the first condition, broth-filled
flasks are sealed and then observed indefinitely. In
the second condition, the flasks are sealed but
eventually broken to demonstrate that spoilage
occurs once external air reaches the broth. The
critical test, between the sealed and broken-neck
flasks, is determined by the Research Design and
the manipulations.9
By modern standards, Pasteur’s description of the
research is somewhat informal. For instance,
although Pasteur mentions that he made multiple
flasks, we do not know how many. For illustrative
purposes, we have inferred details as needed to
complete these examples.
the comparisons that can be made and that must be explicitly
represented.
3.2</p>
    </sec>
    <sec id="sec-21">
      <title>Prototype Interactive Interface</title>
      <p>At the top of the interface, there are several options
to control the features of the visualization. These
include:
The interface was implemented with Python using
the Tk graphics library. Development is ongoing;
the current version is tailored to the specific
example and does not include all the features
needed for other research reports.
3.3</p>
    </sec>
    <sec id="sec-22">
      <title>Hypotheses and the Microworld</title>
    </sec>
    <sec id="sec-23">
      <title>Model</title>
      <p>Because of the complex interaction of entities in
the Microworld, developing the full hypothesis
models required additions to our evolving ontology
and modeling framework. While some air had live
microbes suspended in it, the air in the sealed flask
had no live microbes. Thus, the state of the air is
correlated with its location and the history of that
location.
6

We focus here on Hypothesis1 because it is much
more specific than Hypothesis0. Hypothesis1 is
justified by several claims:</p>
      <p>Microbes can be carried by air currents (0)
Sealing the flask neck blocks outside air (1)
Breaking flask neck allows outside air to enter (2)
High temperatures kill microbes (3)
Microbes feed in a nutrient medium (4)
Microbes will reproduce given food and other
suitable conditions (5)
Metabolism by many microbes results in spoilage
(6)
Earlier research by Pasteur had confirmed (0). The
other claims are largely consistent with common
sense, though they could be tested more
systematically as needed. However, even with
extended testing, it is difficult to make an
unassailable case [21].</p>
      <p>A full executable flow model for Hypothesis1
would be analogous to the flow model in [10].
Note that a model for Hypothesis1 would need to
include models of airflow in the microworld, ad
hoc subregions for the air in the flasks, and
multigranular models that describe transitions of
individual microbes as well as collections of
microbes.</p>
      <p>Because they are yoked, any execution of the
Hypothses1 model should execute the parallel
Researcher Activity model.
3.4</p>
    </sec>
    <sec id="sec-24">
      <title>Outcomes</title>
      <p>Raw data and inferences based on those data can
be collected and organized according to the models
described here. In Pasteur’s study, the key
observation is whether spoilage develops once the
flask neck is broken and microbe-laden air can
enter. That is, the critical test for the Pasteur study
supports Hypothesis1, that the living microbes
carried by air currents lead to spoilage. 10 We did
not model the Actual Outcomes in this case, but we
could have because they could be different than the
predictions of either of the Hypotheses.11
Based on accepting Hypothesis1, we can state two
overall claims:


</p>
      <p>Microbes do not develop spontaneously (7)
Microbes develop from other microbes (8)
Microbes develop only from other microbes of the
same type (8’)
(8’) is a stronger version of (8). Initially, we might
be less willing to accept it, but there are additional
factors we might consider. For instance, flows for
10 We might note the initial observation, that the sealed flasks
show no spoilage. For a more formal confirmation, we could
conduct an additional study with a control group.
11 In [33] the results demonstrated a type of protein binding
that was not predicted by the authors.






the reproductive processes of the microbes would
provide support.</p>
      <p>As noted earlier, the research outcomes need to
satisfy both internal and external validity. Internal
validity concerns what happened because of the
experimental procedure. For instance, we could
dismiss (*9) 12 based on the experience of farmers.
</p>
      <p>A longer time is needed for spoilage to develop than
was used (*9)
(*10) was proposed by Antoine Béchamp, one of
Pasteur’s critics. The claim was that sealing the
flask prevented air with some “vital essence” from
reaching the broth. In a follow-up study, Pasteur
was able to dismiss this criticism with his
wellknown swan-neck flask experiment [26].</p>
      <p>Sealed air loses its vital essence
(*10)
3.5</p>
    </sec>
    <sec id="sec-25">
      <title>Generalizations</title>
      <p>If we combine (6) with (8’) we obtain (11).</p>
      <p>Spoilage due to fermentation can be minimized by
controlling the presence of microbes (11)
This suggests the need for cleanliness to control
contamination in the preparation of fermented
products. Further, if we combine (3) with (11) we
get (12), which is the basis of pasteurization.</p>
      <p>Spoilage due to fermentation can be controlled by
heating the nutrient medium (12)
Joseph Lister generalized (3, 8’, 13) to bacterial
infections to study and promote the need for sterile
surgery. Moreover, adding (14) yields (15).</p>
      <p>Bacteria are a type of microbe (13)
Antiseptics kill bacteria (14)
Bacterial infection can be minimized by antiseptics
(15)
Given the importance of each of these inferences
for humans, presumably additional work would be
done. For instance, specific microbes and the
12 Following a convention in linguistics, the * indicates that
the proposition is incorrect.
details of conditions for growth could be studied
for each medium.
4</p>
    </sec>
    <sec id="sec-26">
      <title>FUTURE WORK</title>
    </sec>
    <sec id="sec-27">
      <title>4.1 Interface, Model, and Claims</title>
      <p>The interface in Figure 1 is adequate for a
straightforward experiment such as Pasteur’s.
However, many modern research papers are much
more complex. For instance, [33] includes a
description of developing a strain of Drosophila
needed for the research. It then conducts a series
of overlapping studies that makes a case for its
conclusions although no one study provides a
definitive test. In such a set of studies, a great
many flows can be identified and modeled. The
interface will need to be improved to provide better
support for that complexity.</p>
      <p>The model and interface should be able to
reorganize the research report flows to fit the
IMRD framework (see Section 2.2). An IMRD
Methods section would include the Research
Design, Procedure, Methods, and Materials. Each
of these components should fit sub-structures or
templates and be integrated into the overall IMRD
framework.</p>
      <p>Claims must be based on clear definitions [12].
We have proposed SUMO as an ontology. SUMO
bases its rules on established definitions, but even
these need to be expanded and refined.</p>
      <p>Although we have related claims to natural
language propositions, our structured approach
does not require natural language. Moreover, the
case roles may be more exactly defined for each
transitional and its interaction with various objects.
In Section 2.6, we suggested that an explanation
for a claim could present a rule and an underlying
mechanism. There is a broader sense of
explanations that they should engage users in a
way that promotes understanding. For instance, an
extension of Figure 1 could support graphical
guided tours as explanations. More elaborate
explanations may be tutorial and can be based on
pedagogical techniques.
Claims from research reports and general axioms
could be collected into a comprehensive
knowledgebase. Although comprehensive, such a
knowledgebase would be fragmented, changing,
and need to represent multiple viewpoints. Even
for areas where there is considerable agreement,
there are internally consistent areas of knowledge
(e.g., Newtonian mechanics) that may be usefully
modeled separately from their connection to
broader models (e.g., quantum mechanics).
Any knowledgebase of claims will need a range of
structured hedges to indicate the type of claim
(conceptual/logical, empirical, etc.), level of
confidence in the claim, and possible criticisms of
it. We would use a preponderance-of-evidence
criterion for the acceptance of claims.</p>
      <p>To the extent that we want to do inference on these
propositions, we will need to support both open
and closed worlds [27] and temporal reasoning in
a dynamic environment [18, 22, 29].</p>
    </sec>
    <sec id="sec-28">
      <title>4.3 Services for the Scientific</title>
    </sec>
    <sec id="sec-29">
      <title>Knowledgebase</title>
      <p>The knowledgebase of research reports and claims
can be viewed as a digital library. In addition to
structured research reports, the library could also
include structured surveys and reviews. Such a
library could be overlaid with services like those
found in a text-based digital library such as
metadata harvesting and search indexing. Because
the contents are structured, daemons may be able
to generate text versions of the reports and to
identify redundancy and inconsistencies.
We emphasize propositions that make claims about
state changes such as (8). In a knowledgebase
these claims should be accompanied by metadata.
The metadata should include basic details such as
date and creator; they should also link to related
claims. If the metadata are said to provide support
for claims, the details of that support should be
included.</p>
      <p>There could be links across structured research
reports that are analogous to citations [5]. Our
focus is at the level of semantics rather than the
characteristics of the documentation. Thus, rather
than link authors, we link functionally and
semantically related flows (e.g., about methods)
that are shared across research reports. In addition,
measures analogous to citation metrics and
altmetrics could be developed for the strength of
claims and the coherence of the knowledgebase
[16].</p>
      <p>Finally, (structured) annotations and commentary
could be added. And administrative and editorial
policies should be developed for managing the
collection.</p>
    </sec>
    <sec id="sec-30">
      <title>4.4 Envoi</title>
      <p>We have proposed using yoked flows to manage
the complexity of scientific research reports and
have presented a prototype of a user interface for
exploring those flows.</p>
      <p>In addition, we have discussed issues for how
claims from empirical scientific research can be
collected and coordinated. The discovery and
evaluation of causal claims are common to other
scientific paradigms [20]. While those other
paradigms may have different procedures than
empirical research, they are also based on flows.
Even if we distinguish classification (e.g.,
identifying different types of microbes) as a
scientific research activity, flows are still used and
could be modeled.</p>
      <p>While we have pointed out some promising
directions, there is still challenging work to be
done in populating and organizing a large
knowledgebase of credible propositions.
5
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  </body>
  <back>
    <ref-list />
  </back>
</article>