<!DOCTYPE article PUBLIC "-//NLM//DTD JATS (Z39.96) Journal Archiving and Interchange DTD v1.0 20120330//EN" "JATS-archivearticle1.dtd">
<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Proxecto Nós: Artificial intelligence at the service of the Galician language</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Adina Ioana Vladu</string-name>
          <email>adina.vladu@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Iria de-Dios-Flores</string-name>
          <email>iria.dedios@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Carmen Magariños</string-name>
          <email>mariadelcarmen.magarinos@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>John E. Ortega</string-name>
          <email>john.ortega@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>José Ramom</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pichel</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Marcos Garcia</string-name>
          <email>marcos.garcia.gonzalez@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Pablo Gamallo</string-name>
          <email>pablo.gamallo@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Elisa Fernández Rei</string-name>
          <email>elisa.fernandez@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Alberto Bugarín</string-name>
          <email>alberto.bugarin.diz@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Manuel</string-name>
          <email>manuel.gonzalez.gonzalez@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>González González</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Senén Barro</string-name>
          <email>senen.barro@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Xosé Luis Regueira</string-name>
          <email>xoseluis.regueira@usc.gal</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Compostela</string-name>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Spain</string-name>
        </contrib>
      </contrib-group>
      <fpage>26</fpage>
      <lpage>30</lpage>
      <abstract>
        <p>Proxecto Nós is an initiative aimed at providing the Galician language with openly licensed resources, tools, and demonstrators in the area of intelligent technologies. The Project has two main scientific and technological objectives: (i) to integrate the Galician language into cuttingedge AI and language technologies, thus enabling the natural use of Galician in human-machine interactions; and (ii) to improve the state of the art of language technologies for Galician. Language technologies, linguistic rights, Galician, low-resource languages.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Proxecto Nós (The Nós Project) is an initiative
promoted by the Galician Government (Xunta de</p>
      <sec id="sec-1-1">
        <title>Galicia),</title>
        <p>aimed
at
providing
the</p>
      </sec>
      <sec id="sec-1-2">
        <title>Galician</title>
        <p>language with openly licensed resources, tools,
demonstrators, and use cases in the area of
intelligent
technologies.</p>
        <p>The
execution
of
Proxecto Nós has been entrusted to the University
being carried out by a research team comprising
members of the Instituto da Lingua Galega (ILG)
and the Centro Singular de Investigación en</p>
      </sec>
      <sec id="sec-1-3">
        <title>Tecnoloxías Intelixentes (CiTIUS).</title>
        <p>The first
stage, spanning from the final trimester of 2021 to
2025, will lay the foundations and provide the
resources that will help place Galician among the
languages that are fully active in the digital
society and economy.</p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>2. Context and motivation</title>
      <p>The development of language technologies is
a strategic innovation area geared towards the
digital society and economy, and it has been a
priority in both Spanish (Plan Estatal de
Investigación Científica y Técnica y de
Innovación, Estrategia Española de Ciencia y
Tecnología y de Innovación) and European
(Horizon 2020) scientific planning. Technologies
such as machine translation (MT), information
extraction (IE), text analytics, and dialogue
systems are essential in the digital society, culture,
and economy.</p>
      <p>Languages in high demand worldwide
(especially English) benefit from a large variety
of computational resources that can contribute to
developing new automatic language processing
technologies and tools. Such is the case due to the
long-standing research tradition in these areas
(e.g., the variety of projects financed by USA’s
DARPA) and the need to incorporate such
languages into the AI applications associated with
the latest electronic devices (such as the
conversational AI or automatic dictation software
developed by Google, Amazon or Apple). Other
languages that have joined AI research later, such
as Chinese, are currently following in the
footsteps of English, through projects such as
Baidu’s Qian Yan, which improve significantly
the computational resources available in their
respective language varieties.</p>
      <p>Notwithstanding, language technologies are
also necessary for languages in lower
international demand. Consequently, different
languages have developed similar initiatives to
Nós. Among others, we can highlight Projecte
AINA, which will develop computational
resources for Catalan until 2024, or the work
carried out at the HiTZ Research Center, focusing
on languages technologies for Basque. Other
projects, such as CorCenCC (in Great Britain, for
Welsh) or UQAILAUT (in Canada, for Inuktitut)
were considered success cases in the promotion of
the digital use of socially threatened languages.</p>
      <p>The democratization of language technologies
has a great social and cultural impact on the
communities that use them. For instance, MT
increases access to contents in different
languages, thus facilitating intercultural relations;
dialogue systems allow us to communicate with
machines in our own language; and semantic
technologies enable advances in the automatic
comprehension of texts, thus making it possible to
process enormous quantities of documents. In the
case of Galician, incorporating the language into
state-of-the-art AI applications can not only
significantly favor its prestige (a decisive factor in
language normalization), but also guarantee
citizens’ language rights and reduce social
inequality.</p>
      <p>
        In economic terms, the global Natural
Language Processing (NLP) market size was
valued at more than USD 10 billion in 2020 and
is expected to reach USD 41 billion by 2025
        <xref ref-type="bibr" rid="ref1">(Aldabe et al., 2021)</xref>
        . NLP technologies are used
in different areas such as information retrieval,
MT, IE (with notable growth in its application in
the medical domain during the Covid-19
pandemic), dialogue systems, and automatic text
generation, among many others. The capacity to
model language, an essential ability for human
beings, ensures a promising future for such
technologies from both an economic and research
and innovation perspective.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. State of the art: Galician resources and technologies</title>
      <p>
        In 2012, the White Paper The Galician
Language in the Digital Age
        <xref ref-type="bibr" rid="ref5">(García-Mateo et al.,
2012)</xref>
        described Galician as a language with a
level of technological support that “gives rise to
cautious optimism”, while highlighting the need
for new resources and tools. Previous research
projects on Galician resulted in speech processing
resources (COTOVÍA), an annotated reference
corpus (CORGA), morphosyntactic lemmatizers
and taggers (XIADA, FreeLing, IXA-Pipes),
other specialized corpora, both text (CLUVI,
CTG. TreeGal) and speech (CORILGA, AGO),
MT systems (GAIO, OpenTrad), spellcheckers
(OrtoGal), grammar checkers (Avalingua),
language analysis and IE tools (Linguakit),
language models (SemantiGal, Bertinho), and
other resources.
      </p>
      <p>
        Furthermore, Galician is currently part of
multilingual crowdsourced data collection
initiatives carried out by important companies on
the global IT market, which have resulted in
speech databases such as Google’s SLR77
        <xref ref-type="bibr" rid="ref8">(Kjartansson et al., 2020)</xref>
        and Mozilla’s
CommonVoice 7.0 and 8.0
        <xref ref-type="bibr" rid="ref2">(Ardila et al., 2020)</xref>
        .
This situation is reflected in a recent report on the
current state of the LT (Language Technology)
field for Galician (Ramírez Sánchez &amp; García
Mateo, 2022), which informed on the
considerable growth in the production of
highquality Galician resources and services, especially
text resources.
      </p>
      <p>
        Despite the quality of these resources, it should
be noted that not all are freely and publicly
available for the development of LT. The LT field
has undergone profound changes over the last few
years since the introduction of neural network
systems. Generally, training models using these
state-of-the-art technologies requires large
quantities of data and has high energetic and
computational costs, which continues to be a
challenge for low-resource languages. However,
as many recent studies show, end-to-end
technologies and open-source multilingual
pretrained models created using large quantities of
data from high-resource languages
        <xref ref-type="bibr" rid="ref3">(Shen et al.,
2018; Baevski et al., 2020; Wolf et al., 2020)</xref>
        can
be used, through transfer learning and fine-tuning,
to train models in low- or medium-resource
languages such as Catalan (Külebi &amp; Öktem,
2018; Külebi et al., 2020) or, in our case, Galician.
To this end, the existence of resources and tools
that are freely available to the scientific and
business community is essential, and that
constitutes one of the main objectives of Proxecto
Nós.
      </p>
    </sec>
    <sec id="sec-4">
      <title>4. Project description</title>
    </sec>
    <sec id="sec-5">
      <title>4.1. Organization</title>
      <p>The tasks that are to be carried out as part of
the Project can be included in the following areas,
corresponding to some of the major NLP fields:
An example of numbered list is as following.
1. Speech synthesis (TTS)
2. Speech recognition (ASR)
3. Automatic text generation
4. Dialogue systems
5. MT
6. IE
7. Opinion mining and fact checking
8. Language correction and assessment
These broad, mutually interdependent areas
fall within the three strategic lines jointly
identified by the Project’s research team and the
Xunta de Galicia (in particular, with the Axencia
para a Modernización Tecnolóxica de Galicia): (i)
spoken or written conversation with people, (ii)
language quality, and (iii) information
management.</p>
      <p>In accordance with the funding agreement
signed by the Xunta de Galicia and the USC, the
organization of the tasks included in Nós follows
a yearly schedule. Each year, resources, language
models and demonstrators from different areas
will be made publicly available.</p>
      <p>More information on the organization of
Proxecto Nós can be found in de-Dios-Flores et
al, 2022.</p>
    </sec>
    <sec id="sec-6">
      <title>4.2. Scientific objectives and technological</title>
      <p>Proxecto Nós has two main scientific and
technological objectives: (i) to integrate the
Galician language into cutting-edge AI and
language technologies, thus enabling the natural
use of Galician in human-machine interactions;
and (ii) to improve the state of the art of language
technologies for Galician.</p>
      <p>For this purpose, resources, tools, and
applications will be developed and distributed
under open licenses, which will allow them to be
integrated into existing devices and services (such
as smart speakers or conversational agents) and
future technologies. To this end, specific
objectives directly related to some of the major
tasks of NLP have been established.</p>
      <p>Each of these technological objectives will be
executed in a different subproject, which will
allow the parallel development of different tasks
and, overall, a more effective organization of the
work. However, a set of general objectives are
shared by all the tasks. These objectives are: (i)
the compilation of high-quality linguistic
resources (annotated reference corpora, web-scale
corpora, specialized corpora by tasks and
domains, parallel corpora, knowledge bases,
dictionaries, etc.); (ii) the elaboration of language
and acoustic models (both general-purpose and
task-specific models); and (iii) the development
of applications based on these models. The project
will also have a general coordination mechanism
through which resources will be distributed and
shared among its subprojects.</p>
      <p>The resources and language models developed
for each task will be made available to the public,
thus allowing their use in all kinds of applications,
services, and products, by the scientific
community, companies, institutions, and society
in general. The results will be disseminated
through a repository available at the project’s web
portal (which can be hosted on internal servers),
as well as other established and internationally
recognized repositories, such as HuggingFace,
GitHub, Zenodo, etc.</p>
      <p>Finally, the project contemplates the complete
development of applications based on these
resources, which will act as visible and accessible
demonstrators of the developed technology and
will produce a tractor effect that will lead to the
development of new products.</p>
    </sec>
    <sec id="sec-7">
      <title>5. Conclusion and future work</title>
      <p>
        Among the initial results of Nós, we can
highlight the first crawl of a web-based Galician
corpus and a language model based on the CCNet
tools and data
        <xref ref-type="bibr" rid="ref10 ref9">(Ortega et al., 2022a)</xref>
        , and the
development and testing of a Spanish-Galician
neural machine translation (NMT) system
prototype
        <xref ref-type="bibr" rid="ref10 ref9">(Ortega et al., 2022b)</xref>
        .
      </p>
      <p>For the current year, Proxecto Nós aims to
keep generating linguistic and computational
resources to explore different subprojects.
Specifically, in the first half of 2022 work will be
carried out on the design of a high-quality speech
corpus of sufficient size so as to allow training
TTS state-of-the-art models, to be released in the
last trimester. The second half of the year will also
see the publication of a speech corpus for ASR. In
the same timeframe, the project will publish
several text corpora: parallel Galician-Spanish,
Galician-English, and Galician-Portuguese
corpora; a web-scale Galician text corpus, larger
than the one already compiled, to be used in all the
subprojects working with written text included in
Nós; and a domain-specific corpus for automatic
text generation. Based on these resources, new
language models will be developed using
different state-of-the-art techniques, as well as
demonstrators or prototypes of a TTS system,
NMT system, and automatic text generator for
Galician. At the same time, throughout 2022
efforts will focus on extending and improving the
first systems developed, and on validating the
results obtained via the creation of high-quality
gold standards.</p>
    </sec>
    <sec id="sec-8">
      <title>Acknowledgements</title>
      <p>This research was funded by the project “Nós:
Galician in the society and economy of artificial
intelligence” (Proxecto Nós: O galego na
sociedade e economía da intelixencia artificial
2021-CP080), agreement between Xunta de
Galicia and University of Santiago de
Compostela, and grant ED431G2019/04 by the
Galician Ministry of Education, University and
Professional Training, and the European Regional
Development Fund (ERDF/FEDER program).
J. Dunne (eds.), Report on the Galician
Language (Deliverable D1.15), ELE, 2022.
[12] J. Shen, R. Pang, R. J. Weiss, M. Schuster,
N. Jaitly, Z. Yang, Z. Chen, Y. Zhang, , Y.
Wang, R. J. Skerry-Ryan, R. A. Saurous, Y.
Agiomyrgiannakis, Y. Wu, Natural TTS
Synthesis By Conditioning Wavenet On Mel
Spectrogram Predictions, in: Proceedings of
ICASSP, 2018.
[13] T. Wolf, L. Debut, V. Sanh, J. Chaumond, C.</p>
      <p>Delangue, A. Moi, P. Cistac, T. Rault, R.
Louf, M. Funtowicz, J. Davison, S. Shleifer,
P. von Platen, C. Ma, Y. Jernite, J. Plu, C.
Xu, T. Le Scao, S. Gugger, et al.,
Transformers: State-of-the-Art Natural
Language Processing. In:  Proceedings of the
2020 Conference on Empirical Methods in
NLP: System Demonstrations, 2020, pp. 38–
45.</p>
    </sec>
  </body>
  <back>
    <ref-list>
      <ref id="ref1">
        <mixed-citation>
          [1]
          <string-name>
            <given-names>I.</given-names>
            <surname>Aldabe</surname>
          </string-name>
          , G. Rehm,
          <string-name>
            <given-names>G.</given-names>
            <surname>Rigau</surname>
          </string-name>
          ,
          <string-name>
            <surname>A. Way,</surname>
          </string-name>
          <article-title>Report on existing strategic documents and projects in LT/AI, European Language Equality (ELE</article-title>
          ),
          <year>2021</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref2">
        <mixed-citation>
          [2]
          <string-name>
            <given-names>R.</given-names>
            <surname>Ardila</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Branson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>K.</given-names>
            <surname>Davis</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Henretty</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Kohler</surname>
          </string-name>
          , J. Meyer,
          <string-name>
            <given-names>R.</given-names>
            <surname>Morais</surname>
          </string-name>
          ,
          <string-name>
            <given-names>L.</given-names>
            <surname>Saunders</surname>
          </string-name>
          ,
          <string-name>
            <given-names>F. M.</given-names>
            <surname>Tyers</surname>
          </string-name>
          , G. Weber,
          <string-name>
            <surname>Common Voice</surname>
            :
            <given-names>A</given-names>
          </string-name>
          <string-name>
            <surname>Massively-Multilingual Speech</surname>
          </string-name>
          Corpus,
          <source>in: Proceedings of LREC</source>
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref3">
        <mixed-citation>
          [3]
          <string-name>
            <given-names>A.</given-names>
            <surname>Baevski</surname>
          </string-name>
          ,
          <string-name>
            <given-names>H.</given-names>
            <surname>Zhou</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Mohamed</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Auli</surname>
          </string-name>
          , wav2vec
          <volume>2</volume>
          .
          <article-title>0: A Framework for SelfSupervised Learning of Speech Representations</article-title>
          . arXiv,
          <year>2020</year>
          , pp.
          <fpage>1</fpage>
          -
          <lpage>19</lpage>
          . doi:
          <volume>10</volume>
          .48550/arXiv.
          <year>2006</year>
          .11477
        </mixed-citation>
      </ref>
      <ref id="ref4">
        <mixed-citation>
          [4] I.
          <string-name>
            <surname>de-Dios-Flores</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          <string-name>
            <surname>Magariños</surname>
            ,
            <given-names>A. I.</given-names>
          </string-name>
          <string-name>
            <surname>Vladu</surname>
            ,
            <given-names>J. E.</given-names>
          </string-name>
          <string-name>
            <surname>Ortega</surname>
            ,
            <given-names>J. R.</given-names>
          </string-name>
          <string-name>
            <surname>Pichel</surname>
            ,
            <given-names>M.</given-names>
          </string-name>
          <string-name>
            <surname>García</surname>
            ,
            <given-names>P.</given-names>
          </string-name>
          <string-name>
            <surname>Gamallo</surname>
            ,
            <given-names>E. Fernández</given-names>
          </string-name>
          <string-name>
            <surname>Rei</surname>
            ,
            <given-names>A.</given-names>
          </string-name>
          <string-name>
            <surname>Bugarín-Diz</surname>
            ,
            <given-names>M. González</given-names>
          </string-name>
          <string-name>
            <surname>González</surname>
            ,
            <given-names>S.</given-names>
          </string-name>
          <string-name>
            <surname>Barro</surname>
            ,
            <given-names>X. L.</given-names>
          </string-name>
          <string-name>
            <surname>Regueira</surname>
          </string-name>
          , The Nós Project:
          <article-title>Opening routes for the Galician language in the field of language technologies</article-title>
          ,
          <source>in: Proceedings of the TDLE Workshop @LREC2022</source>
          , pp.
          <fpage>52</fpage>
          -
          <issue>61</issue>
          <year>Marseille</year>
          ,
          <issue>20</issue>
          <year>June 2022</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref5">
        <mixed-citation>
          [5]
          <string-name>
            <given-names>C.</given-names>
            <surname>García Mateo</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Arza</surname>
          </string-name>
          <article-title>Rodríguez (auth</article-title>
          .), G. Rehm, H. Uszkoreit (eds.),
          <article-title>The Galician Language in the Digital Age</article-title>
          , SpringerVerlag, Berlin Heidelberg,
          <year>2012</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref6">
        <mixed-citation>
          [6]
          <string-name>
            <given-names>B.</given-names>
            <surname>Külebi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Öktem</surname>
          </string-name>
          ,
          <article-title>Building an Open Source Automatic Speech Recognition System for Catalan</article-title>
          , in: IberSPEECH, Barcelona, Spain,
          <year>2018</year>
          , pp.
          <fpage>25</fpage>
          -
          <lpage>29</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref7">
        <mixed-citation>
          [7]
          <string-name>
            <given-names>B.</given-names>
            <surname>Külebi</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Öktem</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Peiró-Lilja</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Pascual</surname>
          </string-name>
          ,
          <string-name>
            <given-names>M.</given-names>
            <surname>Farrús</surname>
          </string-name>
          ,
          <string-name>
            <surname>CATOTRON - A Neural</surname>
          </string-name>
          Text
          <article-title>-To-Speech System in Catalan</article-title>
          .
          <source>In: Proceedings of Interspeech</source>
          <year>2020</year>
          .
        </mixed-citation>
      </ref>
      <ref id="ref8">
        <mixed-citation>
          [8]
          <string-name>
            <given-names>O.</given-names>
            <surname>Kjartansson</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Gutkin</surname>
          </string-name>
          ,
          <string-name>
            <given-names>A.</given-names>
            <surname>Butryna</surname>
          </string-name>
          , I. Demirsahin,
          <string-name>
            <given-names>C.</given-names>
            <surname>Rivera</surname>
          </string-name>
          ,
          <article-title>Open-Source High Quality Speech Datasets for Basque, Catalan and Galician</article-title>
          ,
          <source>in: Proceedings of the 1st Joint Workshop on SLTU and CCURL</source>
          , Marseille, France,
          <year>2020</year>
          , pp.
          <fpage>21</fpage>
          -
          <lpage>27</lpage>
          .
        </mixed-citation>
      </ref>
      <ref id="ref9">
        <mixed-citation>
          [9]
          <string-name>
            <given-names>J. E.</given-names>
            <surname>Ortega</surname>
          </string-name>
          , I. de Dios Flores,
          <string-name>
            <given-names>P.</given-names>
            <surname>Gamallo</surname>
          </string-name>
          ,
          <string-name>
            <given-names>J. R.</given-names>
            <surname>Pichel</surname>
          </string-name>
          ,
          <string-name>
            <surname>A</surname>
          </string-name>
          <article-title>Neural Machine Translation System for Spanish to Galician through Portuguese Transliteration</article-title>
          ,
          <source>in: PROPOR</source>
          <year>2022</year>
          , Fortaleza, Brazil.
        </mixed-citation>
      </ref>
      <ref id="ref10">
        <mixed-citation>
          [10]
          <string-name>
            <given-names>J. E.</given-names>
            <surname>Ortega</surname>
          </string-name>
          , I. de Dios Flores,
          <string-name>
            <given-names>J. R.</given-names>
            <surname>Pichel</surname>
          </string-name>
          ,
          <string-name>
            <given-names>P.</given-names>
            <surname>Gamallo</surname>
          </string-name>
          ,
          <article-title>Revisiting CCNet for Quality Measurements in Galician</article-title>
          ,
          <source>in: PROPOR</source>
          <year>2022</year>
          , Fortaleza, Brazil.
        </mixed-citation>
      </ref>
      <ref id="ref11">
        <mixed-citation>
          [11]
          <string-name>
            <surname>J. M. Ramírez Sánchez</surname>
            ,
            <given-names>C.</given-names>
          </string-name>
          <article-title>García Mateo (auth</article-title>
          .),
          <string-name>
            <given-names>M.</given-names>
            <surname>Giagkou</surname>
          </string-name>
          ,
          <string-name>
            <given-names>S.</given-names>
            <surname>Piperidis</surname>
          </string-name>
          , G. Rehm,
        </mixed-citation>
      </ref>
    </ref-list>
  </back>
</article>