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: "a new era in citation and bibliometric analyses web of science scopus and google scholar"
  Abstract: Academic institutions, federal agencies, publishers, editors, authors, and librarians increasingly rely on citation analysis for making hiring, promotion, tenure, funding, and/or reviewer and journal evaluation and selection decisions. The Institute for Scientific Information's (ISI) citation databases have been used for decades as a starting point and often as the only tools for locating citations and/or conducting citation analyses. ISI databases (or Web of Science), however, may no longer be adequate as the only or even the main sources of citations because new databases and tools that allow citation searching are now available. Whether these new databases and tools complement or represent alternatives to Web of Science (WoS) is important to explore. Using a group of 15 library and information science faculty members as a case study, this paper examines the effects of using Scopus and Google Scholar (GS) on the citation counts and rankings of scholars as measured by WoS. The paper discusses the strengths and weaknesses of WoS, Scopus, and GS, their overlap and uniqueness, quality and language of the citations, and the implications of the findings for citation analysis. The project involved citation searching for approximately 1,100 scholarly works published by the study group and over 200 works by a test group (an additional 10 faculty members). Overall, more than 10,000 citing and purportedly citing documents were examined. WoS data took about 100 hours of collecting and processing time, Scopus consumed 200 hours, and GS a grueling 3,000 hours.

Connected through hyperedge HE-1 (induced by source paper "benchmarking some portuguese s t system research units 2nd edition"):
  with members:
    - "benchmarking some portuguese s t system research units"
    - "scientific impact quantity and quality analysis of two sources of bibliographic data"

Connected through hyperedge HE-2 (induced by source paper "benchmarking some portuguese s t system research units"):
  with members:
    - "scientific impact quantity and quality analysis of two sources of bibliographic data"

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)