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: "e prints and journal articles in astronomy a productive co existence"
  Abstract: Are the e-prints (electronic preprints) from the arXiv repository being used instead of journal articles? We show that the e-prints have not undermined the usage of journal papers from the four core journals in astrophysics. As soon as the journal article is published, the astronomical community prefers to read it and the use of e-prints through the NASA Astrophysics Data System drops to zero. This suggests that most astronomers have access to institutional subscriptions and that they choose to read the journal article. In other words, the e-prints have not undermined journal use in this community and thus currently do not pose a financial threat to publishers. Furthermore, we show that the half-life (the point at which the use of an article drops to half the use of a newly published article) for an e-print is shorter than for a journal paper.

Connected through hyperedge HE-1 (induced by source paper "quantifying the cognitive extent of science"):
  with members:
    - "inheritance patterns in citation networks reveal scientific memes"
    - "growth rates of modern science a bibliometric analysis based on the number of publications and cited references"

Connected through hyperedge HE-2 (induced by source paper "arxiv e prints and the journal of record an analysis of roles and relationships"):
  with members:
    - "last but not least additional positional effects on citation and readership in arxiv"
    - "citing and reading behaviours in high energy physics how a community stopped worrying about journals and learned to love repositories"
    - "positional effects on citation and readership in arxiv"
    - "does the arxiv lead to higher citations and reduced publisher downloads for mathematics articles"
    - "the convergence of digital libraries and the peer review process"
    - "the effect of use and access on citations"
    - "scholarly communication and the continuum of electronic publishing"

Connected through hyperedge HE-3 (induced by source paper "the potential of preprints to accelerate scholarly communication a bibliometric analysis based on selected journals"):
  with members:
    - "does the arxiv lead to higher citations and reduced publisher downloads for mathematics articles"
    - "the convergence of digital libraries and the peer review process"

Connected through hyperedge HE-4 (induced by source paper "use of astronomical literature a report on usage patterns"):
  with members:
    - "worldwide use and impact of the nasa astrophysics data system digital library"

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)