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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Games and gamification in flipped classrooms: A systematic review</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Annique Smith</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Nikoletta Zampeta Legaki</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Juho Hamari</string-name>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Information Science, Virtual Reality and Interaction Lab, University of Pretoria</institution>
          ,
          <addr-line>2 Lynnwood Road, Pretoria, 0181</addr-line>
          ,
          <country country="ZA">South Africa</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Gamification Group, Tampere University</institution>
          ,
          <addr-line>Kalevantie 4, 33100, Tampere</addr-line>
          ,
          <country country="FI">Finland</country>
        </aff>
      </contrib-group>
      <fpage>33</fpage>
      <lpage>43</lpage>
      <abstract>
        <p>The landscape of education is experiencing a shift towards active learning approaches as the need for independent, lifelong learning increases. Traditional lecture-based teaching methodologies are not as effective at keeping students motivated enough to engage with content on a deep level. Therefore, approaches such as student-centred learning, self-directed learning, and flipped classrooms are becoming more popular as educators begin to embrace the idea of giving students more autonomy in the classroom. The popularity of gamification and games in education has led to them being used in conjunction with these active learning methods, however this area lacks a high-level view of present and future work. This study aims to bring clarity to this area of education by presenting a systematic review of the use of games and gamification in flipped classrooms. In general, the results show that current implementations have had positive outcomes, especially in terms of academic performance. The data also shows that the in-class component of flipped classrooms is more commonly gamified compared to the out-of-class component, and that achievement affordances and Kahoot! are popular motivational affordances to use. Further research is proposed concerning social affordances and increased reliance on theoretical foundations.</p>
      </abstract>
      <kwd-group>
        <kwd>1 Gamification</kwd>
        <kwd>game-based learning</kwd>
        <kwd>flipped classroom</kwd>
        <kwd>autonomous education</kwd>
        <kwd>systematic review</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        The rapid advancement of technology in recent
years has resulted in an increasing need for
students to develop lifelong learning skills which
will allow them to be adaptable in the working
world [
        <xref ref-type="bibr" rid="ref1 ref2">1,2</xref>
        ]. This is also reflected in the fourth
sustainable development goal (SDG #42) which
calls for lifelong learning opportunities for all.
Some of the core competencies required for
lifelong learning include self-management,
learning how to learn, and information acquisition
skills [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Educators are realising that the best way
to impart these kinds of skills is through active
learning methodologies which are more capable
of encouraging students to engage with content on
a deeper level than traditional lecture-based
methods [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        Three educational approaches related to active
learning are self-directed learning (SDL),
studentcentred learning (SCL), and flipped classrooms
(FC). SDL is an approach to teaching in which
students function autonomously, taking a large
amount of responsibility for their own learning
[
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Closely related to this is SCL, an approach to
teaching in which the power of the learning
process is shifted from the teacher to the student,
thus giving the learner more control and
responsibility [
        <xref ref-type="bibr" rid="ref5 ref6">5,6</xref>
        ]. Finally, the flipped classroom
model involves moving the traditional teaching
activities which are more passive to outside the
classroom so that class time can be used for more
active learning methods [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. All three of these
approaches involve a move away from traditional
lecture-based teaching practices towards active
learning methods. In the process, the learner
becomes more autonomous, which can result in
improved lifelong learning skills [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. These types
of educational approaches have grown in
popularity, and the COVID-19 pandemic has
served to increase educators’ reliance on
nontraditional methods [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>
        While these approaches all have the potential
to improve learning outcomes, it remains difficult
to motivate learners to take more responsibility
for their learning since this requires more effort
and it challenges their ideas of how teaching
should work (that the teacher should be in charge)
[
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]. Games have been shown to be capable of
motivating players effectively, according to
selfdetermination theory [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. As an offshoot of this,
gamification and game-based learning (GBL)
have been explored as a means by which the
motivation of learners in educational contexts
might be improved [
        <xref ref-type="bibr" rid="ref12 ref13">12,13</xref>
        ].
      </p>
      <p>
        In order to position this study within the field
of gamification, it is necessary to clarify our
perspective with regards to the distinction
between gamification and game-based learning.
Within the literature, the difference is usually
described in terms of parts or whole. In other
words, game-based learning is considered a full
game while gamification consists only of parts of
a game [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. However, we hold to the definition
of gamification provided by [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] which describes
the term as an umbrella concept encompassing
any technology or practice which gives rise to
experiences akin to games. Therefore, we will
refer to both concepts as being part of the category
of gamification for the remainder of this paper.
      </p>
      <p>
        Given the broad definition of gamification, its
potential to positively impact learning outcomes
and motivation is a common area of research [
        <xref ref-type="bibr" rid="ref17 ref18 ref19">17,
18, 19</xref>
        ]. However, there is a dearth of studies that
document the use of these approaches in
conjunction with methods such as flipped
classrooms or for making a course more
studentcentred [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. As a result, it is not yet clear how
GBL and gamification are being used in these
areas and what the outcomes of these applications
are.
      </p>
      <p>Therefore, in the interest of understanding the
intersection between games and gamification in
autonomous learning contexts, a systematic
literature review was conducted. It focused on
student-centred learning, self-directed learning,
and flipped classrooms, and the ways in which
games and gamification have been used in
conjunction with these teaching methodologies.
This article presents the results of a subsection of
articles analysed in the review, focusing
specifically on the use of games and gamification
in flipped classrooms in order to describe the
current state of this specific area of education.</p>
      <p>
        When framed as an approach to active
learning, the flipped classroom model is
concerned with making better use of the time that
students spend in contact with one another and
with the teacher. This requires moving
information-transmission teaching out of the
class. This can serve to increase the autonomy of
students by giving them more control over their
own learning [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. The flipped classroom can also
be viewed as a means of democratising the
classroom by making students contributors to the
learning process [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ]. From this critical pedagogy
perspective, it is about more than simply creating
independent learners, but about challenging the
traditional view of educational settings in which
an expert assumes complete ignorance in their
student audience and takes it upon themself to
remedy this [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. As a result of doing away with
passive teaching, the progressive teaching
principles espoused by Dewey [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ] can be
adopted, thus creating the opportunity for students
to become open-minded, flexible, and valuable
contributors of society.
      </p>
      <p>
        The flipped classroom model’s success relies
upon students being motivated enough to spend
significant amounts of time on out-of-class work
[
        <xref ref-type="bibr" rid="ref21 ref25">21,25</xref>
        ]. Gamification has been used in both the
in-class and out-of-class components of a flipped
classroom, whether as a means of motivating
students to prepare for class [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] or as a way of
actively engaging them during class [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ].
      </p>
      <p>
        To the best of our knowledge, one other review
on gamification in flipped classrooms exists [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ].
Our review seeks to expand upon this contribution
by also investigating the use of full games in
flipped classrooms as well as conducting the
search two years later. In addition, we aim to
investigate the component of the flipped
classroom which was gamified (in- or
out-ofclass) and the types of study designs which were
used.
      </p>
      <p>The remainder of this paper is structured as
follows: section 2 describes the methodology
followed for the review; section 3 presents the
results; section 4 provides a discussion of the
applicability of these results; and section 5
concludes the paper by outlining future work.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Review process</title>
      <p>
        The review was conducted according to the
guidelines for an effective review [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ]. The
following section describes the steps that were
followed during the review process, which is
shown in Figure 1.
      </p>
      <p>The literature search was conducted using the
Scopus database. It was chosen because it is
known to index many publishers, including those
most relevant to this field of inquiry (IEEE, ACM,
and Springer). The search query was constructed
to address the intersection of games and
gamification with three main areas of learning
considered to be more autonomous than
traditional educational experiences – flipped
classrooms, SCL, and SDL. The search was
conducted using the following search string in
April 2021:</p>
      <p>TITLE-ABS-KEY (game* OR gamif*)
AND
(((flipped* OR inverted*) AND (class* OR
learning OR education OR instruction OR
teaching))</p>
      <p>OR
({self-directed learning} OR {self-directed
instruction} OR {self-directed education} OR
{self-directed teaching} OR {self-managed
learning} OR {self-managed instruction} OR
{self-managed education} OR {self-managed
teaching} OR {independent learning} OR
{independent instruction} OR {self-initiated
learning} OR {self-initiated education} OR
{selfinitiated instruction})</p>
      <p>OR
("student centered" OR "student centred" OR
"learner centered" OR "learner centred")).</p>
      <p>The asterisk (*) was used in the search query
to ensure that all variations of a term are included.
For example, “gamification” as well as
“gamified” would fit the query.
2.1.</p>
    </sec>
    <sec id="sec-3">
      <title>Inclusion and exclusion criteria</title>
      <p>The search was limited to English papers from
journals and conferences, as well as book
chapters. The inclusion criteria for papers were:
1. Either games or gamification had to be
used in conjunction with flipped learning or for
the purpose of making a course more
studentcentred or students more self-directed (54
papers excluded).
2. The game or gamification had to be
described in enough detail to allow it to be
mapped, i.e., the main parts are described in
order to allow the motivational affordances to
be mapped by the reviewer (10 papers
excluded).
3. The study had to include empirical results
(descriptions of interventions which did not
report results from testing were therefore
excluded) (159 papers excluded).
4. If the paper was concerned with SCL or
SDL, it had to engage with the concept by
describing it in greater detail in the body of the
paper instead of only mentioning it in the
abstract or keywords (33 papers excluded).
In addition, papers were excluded if:
1. They did not describe a formal education
setting such as a kindergarten or school
(K12) or a tertiary education environment
(informal adult education and studies
involving students outside of a formal
course were excluded) (58 papers
excluded).
2. They were concerned with situations
where students created their own games to
learn (10 papers excluded)
3. They were studies about students’
opinions about teaching methods without
any actual changes to a course/classroom
(6 papers excluded).</p>
      <p>After applying the above-mentioned criteria,
92 papers remained for analysis (58.7% about
flipped classroom; 21.7% about SCL; 14.1%
about SDL; 4.3% about flipped classroom and
SCL, and 1.1% about flipped classroom and
SDL). The full list of included papers is available
here: https://bit.ly/3lRelj0. This article focuses
only on those papers relating to flipped classroom
approaches. An analysis of the full sample will be
the subject of future work.</p>
      <p>
        Based on the guidelines of [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ], a
conceptcentric matrix was used to map the details of each
paper. To prevent the introduction of bias, details
such as motivational affordances and study
outcomes were mapped as described by the
authors without further analysis from the
reviewer. The review process was conducted by
the first author of this paper. Any mapping
decisions were discussed amongst the research
team.
      </p>
    </sec>
    <sec id="sec-4">
      <title>3. Results</title>
      <p>As mentioned before, this article will focus
only on papers relating to flipped classroom
environments (59 papers; 64.1% of the sample). It
should be noted that one paper presented two
studies which were mapped separately, hence the
total number of studies included in the sample
presented in this article is 60.</p>
      <p>
        The presentation of the results will begin with
an overview of the demographic data of the
studies. Following this are the details of the
motivational affordances used, the results of
experimental studies and the parts of the flipped
classroom that were modified by games and
gamification. The terminology relating to
motivational affordances and study outcomes is
the same as that outlined by [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ].
3.1.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Demographic details</title>
      <p>The popularity of using games and
gamification in flipped classrooms has been
steadily increasing since 2016, as shown in Figure
2. In 2020, the last full year that was reviewed in
this study, the number of publications almost
doubled from the previous two years.</p>
      <p>Figure 2: The number of papers published per
year (N = 59)</p>
      <p>Most of the studies were conducted in Asia and
Europe, with these contributing 18 papers each
(30%), while studies in North America amounted
to 8 papers (13.3%) and Africa, the Middle east
and South America were each represented by 1
paper (1.7%). 13 studies (21.7%) did not specify
where they were conducted.</p>
      <p>
        Games and gamification have been employed
in a wide variety of fields, as shown in Table 1,
with computing being the most popular at a
tertiary level. This could be because teachers of
computing content are more likely to be
comfortable with adding digital elements to their
courses [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ], and this is in line with other reviews
on gamification in education [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. At a K12 level
(kindergarten to twelfth grade), social science and
science are the main fields being gamified. Lastly,
the use of gamification in flipped classrooms is
more common at tertiary level
(university/college) than at school level.
      </p>
      <p>Table 2 shows the types of studies which have
been employed – whether the game/gamification
was combined with flipped classroom and then
tested against a control of flipped classroom or a
traditional class, or whether the gameful
components were simply used as part of a flipped
classroom, sometimes along with other
educational approaches such as collaboration,
peer instruction, and blended learning. The “other
settings” study design includes several unique
study design types (described below the table).</p>
    </sec>
    <sec id="sec-6">
      <title>3.3. Experimental studies, affordances, and outcomes</title>
    </sec>
    <sec id="sec-7">
      <title>3.2. Motivational affordances and study designs</title>
      <p>
        Table 2 also shows the motivational
affordances used (according to the mapping by
[
        <xref ref-type="bibr" rid="ref29">29</xref>
        ]). The most used achievement affordances
were points (18 studies; 30%), badges (15 studies;
25%), and leaderboards (13 studies; 21.6%). This
also reflected other reviews of the use of
gamification in education [
        <xref ref-type="bibr" rid="ref17 ref30">17,30</xref>
        ]. Social
affordances included teamwork (9 studies; 15%)
and competition (9 studies; 15%), while the most
common immersion affordances were the use of
narrative (8 studies; 13.3%) and role play (6
studies; 10%). The most common non-digital
elements were physical dice (6 studies; 10%) and
physical playboards and/or tokens (5 studies;
8.3%). These were often employed together in the
form of boardgames. Finally, miscellaneous
affordances included full commercial games or
systems (such as Kahoot!, Socrative or word
games). 27 studies (45%) used such games, with
14 (23%) of those using Kahoot!
      </p>
      <p>The class component item in Table 2 describes
which part of the flipped classroom was modified
to include the motivational affordances. It tended
to be more common to modify the in-class
component of the course. This could be because
motivational affordances could more easily be
included in these settings, whereas out-of-class
settings would require a digital system to keep
track of student activity and provide access to the
gameful components.
.</p>
      <p>23 studies (38.3%) were classified as
experimental studies according to the following
criteria:
1.</p>
      <p>Clearly defined hypothesis or research
question.
2. The use of a control group or pre-post-test
design
3. The use of inferential statistics.</p>
      <p>Figure 3 shows the mapping of these
experimental studies according to the
motivational outcomes used and the outcome of
the study. Positive results imply that the applied
motivational affordances resulted in
improvements to the specific measured outcomes.
Mixed results were mapped according to whether
the majority of tests had yielded positive or
negative results (negative meaning that the
applied affordances had no significant measurable
effect on the outcomes). Most of the studies
reported positive results, i.e., the applied
motivational affordances resulted in
improvements to the specific measured outcomes,
with achievement affordances and miscellaneous
elements being the most popular affordances
implemented. Most of the miscellaneous
affordances used in experimental studies (8
studies out of 11) were full games.</p>
      <p>In terms of the specific types of outcomes that
were measured, across all 60 studies the highest
measured outcomes were psychological states (25
studies; 41.6%), such as motivation and attitude
towards the course content; and performance
outcomes (38 studies, 63.3%), such as the level of
academic performance, quality of work and level
of participation in the course. Figure 4 shows the
results of experimental studies organized
according to outcome type. The popularity of
psychological and performance outcomes is also
visible here, and educational performance
outcomes showed primarily positive results.
Furthermore, there are some cases where studies
reported no positive changes where games and
gamification were added to a flipped classroom.</p>
    </sec>
    <sec id="sec-8">
      <title>4. Discussion</title>
      <p>Overall, the results suggest that games and
gamification can have a positive effect in flipped
classrooms, especially with regards to
performance outcomes such as academic
achievement.</p>
      <p>
        The analysis revealed that more than one-third
of the studies employed the design of combining
games/gamification with the flipped classroom
without a control group. While the use of a
pre/post-test in these contexts made it possible to
gauge whether the course was improved by the
addition of the gamification, it was impossible to
conclusively attribute the outcome to the
gamification (compared to studies where a
nongamified control group was used). According to
[
        <xref ref-type="bibr" rid="ref31">31</xref>
        ], the design of the instructional materials in a
flipped classroom have a great influence on the
way in which students perceive the learning
content. Therefore, it is recommended that future
research involves more experimental designs with
control groups to make it possible to isolate the
effects of the gamification treatment.
      </p>
      <p>
        Furthermore, the use of points, badges, and
leaderboards (PBLs) as the most common
affordances remains in line with other reviews on
gamification in education. As shown by [
        <xref ref-type="bibr" rid="ref32">32</xref>
        ], the
use of PBLs may not always be suitable for the
context in which they are employed. For example,
leaderboards have contributed to a number of
negative effects in gamification studies [
        <xref ref-type="bibr" rid="ref32">32</xref>
        ].
PBLs fall under the category of achievement
affordances [
        <xref ref-type="bibr" rid="ref33">33</xref>
        ]. The much lower incidence of
immersion- and social-related affordances in the
sample analysed indicates a gap in the field which
also echoes the state of gamification across other
fields [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ]. The flipped classroom model makes it
possible to utilise class time for more interactive,
social learning activities such as group work and
discussions [
        <xref ref-type="bibr" rid="ref34">34</xref>
        ]. In this sense, it may be simpler
to implement social affordances in this kind of
classroom setting when compared to traditional
classes. As such, flipped classrooms are
wellplaced to contribute to the field of gamification in
this way [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ]. In terms of the use of full games in
flipped classrooms, Kahoot! was the primary
choice for in-class engagement. The features of
this system – free to access and easy to use – make
it the ideal companion to in-class activities.
2
2
4
3
1
4
2
1
3
1
1
12
2
3
5
2
2
1
5
1
1
1
1
12
      </p>
      <p>Non-digital
elements
1
1
2
2
3
1
4
1
1
2
9</p>
      <p>
        A literature review by [
        <xref ref-type="bibr" rid="ref35">35</xref>
        ] reports that
Kahoot! can have a positive effect on learning
when compared to other approaches. It also
embraces the bring-your-own-device (BYOD)
model which is already popular in education,
especially at a tertiary level [
        <xref ref-type="bibr" rid="ref36">36</xref>
        ]. The studies that
employed Kahoot! in the classroom used it mainly
as a type of formative assessment to consolidate
knowledge that students would have gained from
engaging with the out-of-class material [
        <xref ref-type="bibr" rid="ref37 ref38">37,38</xref>
        ].
      </p>
      <p>
        In general, the in-class component received
more attention in terms of the use of games and
gamification. Since the flipped classroom model
only works if students prepare adequately for
class, the use of motivational affordances to
encourage this behaviour is an interesting line of
inquiry which requires additional investigation
[
        <xref ref-type="bibr" rid="ref20">20</xref>
        ].
      </p>
      <p>
        The studies analysed reported few negative
effects from the gamified interventions, although
[
        <xref ref-type="bibr" rid="ref39">39</xref>
        ] reported that some students gamed the
system in order to earn more badges. This is one
of the known negative effects of gamification
[
        <xref ref-type="bibr" rid="ref32">32</xref>
        ]. [
        <xref ref-type="bibr" rid="ref40">40</xref>
        ] found that the students only interacted
with the gamified elements due to the competition
they created, not because they associated it with
improved learning. It is because of cases like these
that it is important that the motivational
affordances be intrinsically tied to the learning
content to prevent students from bypassing the
learning content while engaging with the game
elements [
        <xref ref-type="bibr" rid="ref16 ref41">16,41</xref>
        ].
      </p>
      <p>
        Finally, in terms of methodological
approaches, the sample analysed contained no
studies which attempted to isolate individual
affordances to test their effectiveness. Within the
field of gamification, calls have been made for
these kinds of studies in order to understand how
gamification works [
        <xref ref-type="bibr" rid="ref29 ref42">29,42</xref>
        ], and testing the effects
of individual affordances is one of the main ways
to achieve this. In addition, the current reliance on
academic achievement as an outcome measure,
while being the simplest way to determine
whether an intervention has been effective, misses
a deeper understanding of exactly how it has
resulted in improved performance. A focus on
measures such as psychological outcomes
(motivation, attitude towards the content,
selfregulation, engagement, confidence etc.)
combined with engagement outcomes, such as
time spent interacting with the motivational
affordances, could shed light on the specific ways
in which these affordances function to bring about
improved performance from students.
      </p>
      <p>
        The studies included also showed very little
reliance on underlying theoretical work, such as
self-determination theory or theories of
engagement. In order to support the understanding
of how gamification works in different contexts,
it is important to base empirical work on firm
theoretical assumptions [
        <xref ref-type="bibr" rid="ref43">43</xref>
        ].
      </p>
    </sec>
    <sec id="sec-9">
      <title>5. Limitations</title>
      <p>As with any study, this one is not without its
limitations. Firstly, the search was limited to the
Scopus database. The number of articles retrieved
for the final analysis (92 articles in the full
sample) is fairly substantial and Scopus is
considered to index the most relevant publishers
in this field. While this may serve to curtail the
effect of this limitation on the findings, it is
possible that some publications may have been
missed, especially since snowball sampling was
not conducted to find additional related studies.
Secondly, the search string used may not have
been sufficient to retrieve all possible matches to
the query. To mitigate this limitation, the search
string was revised and refined over several
iterations to ensure that, as far as possible, all
conceivable variations of the search terms were
addressed.</p>
    </sec>
    <sec id="sec-10">
      <title>6. Concluding remarks</title>
      <p>This study has provided a systematic analysis
of studies concerning the use of games or
gamification in flipped classrooms within formal
education settings. This is an emerging field of
inquiry and could benefit from high-level
overviews of prior work.</p>
      <p>The results show that educators are beginning
to embrace the idea of using games and
gamification in flipped classrooms, with
inclassroom activities being the primary focus. The
outcomes of these studies are mostly positive,
although mainly achievement affordances were
used, and performance-based outcomes were
tested. There is much room for variety in these
areas.</p>
      <p>These results contribute to the current
understanding of the state of the field. Future
work includes reporting on the full set of studies
that were returned in the search query to gain a
broader perspective on the use of games and
gamification for autonomous learning.</p>
    </sec>
    <sec id="sec-11">
      <title>7. References</title>
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