human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "an approach to the author citation potential measures of scientific performance which are invariant across scientific fields"
  Abstract: The citation potential is a measure of the probability of being cited. Obviously, it is different among fields of science, social science, and humanities because of systematic differences in publication and citation behaviour across disciplines. In the past, the citation potential was studied at journal level considering the average number of references in established groups of journals (for example, the crown indicator is based on the journal subject categories in the Web of Science database). In this paper, some characterizations of the author?s scientific research through three different research dimensions are proposed: production (journal papers), impact (journal citations), and reference (bibliographical sources). Then, we propose different measures of the citation potential for authors based on a proportion of these dimensions. An empirical application, in a set of 120 randomly selected highly productive authors from the CSIC Research Centre (Spain) in four subject areas, shows that the ratio between production and impact dimensions is a normalized measure of the citation potential at the level of individual authors. Moreover, this ratio reduces the between-group variance in relation to the within-group variance in a higher proportion than the rest of the indicators analysed. Furthermore, it is consistent with the type of journal impact indicator used. A possible application of this result is in the selection and promotion process within interdisciplinary institutions, since it allows comparisons of authors based on their particular scientific research.

Connected through hyperedge HE-1 (induced by source paper "publication modalities article in press and open access in relation to journal average citation"):
  with members:
    - "prevalence and citation advantage of gold open access in the subject areas of the scopus database"
    - "influencia de la fecha de publicacion online de los articulos cientificos en los indicadores bibliometricos"
    - "reconsidering the gold open access citation advantage postulate in a multidisciplinary context an analysis of the subject categories in the web of science database 2009 2014"
    - "the open access advantage considering citation article usage and social media attention"
    - "comparing journals from different fields of science and social science through a jcr subject categories normalized impact factor"
    - "self selected or mandated open access increases citation impact for higher quality research"
    - "the effect of use and access on citations"

Connected through hyperedge HE-2 (induced by source paper "prevalence and citation advantage of gold open access in the subject areas of the scopus database"):
  with members:
    - "reconsidering the gold open access citation advantage postulate in a multidisciplinary context an analysis of the subject categories in the web of science database 2009 2014"
    - "the open access advantage considering citation article usage and social media attention"
    - "comparing journals from different fields of science and social science through a jcr subject categories normalized impact factor"
    - "self selected or mandated open access increases citation impact for higher quality research"
    - "the effect of use and access on citations"

Question: Please tell me which class the center node belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.DL(Digital Libraries)