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: "h index of scientific nursing journals according to google scholar metrics 2007 2011"
  Abstract: The aim of this report is to present a ranking of Nursing journals covered in Google Scholar Metrics (GSM), a Google product launched in 2012 to assess the impact of scientific journals from citation counts this receive on Google Scholar. Google has chosen to include only those journals that have published at least 100 papers and have at least one citation in a period of five years (2007-2011). Journal rankings are sorted by languages (showing the 100 papers with the greatest impact). This tool allows to sort by subject areas and disciplines, but only in the case of journals in English. In this case, it only shows the 20 journals with the highest h index. This option is not available for journals in the other nine languages present in Google (Chinese, Portuguese, German, Spanish, French, Korean, Japanese, Dutch and Italian). #R##N#Google Scholar Metrics doesnt currently allow to group and sort all journals belonging to a scientific discipline. In the case of Nursing, in the ten listings displayed by GSM we can only locate 34 journals. Therefore, in an attempt to overcome this limitation, we have used the diversity of search procedures allowed by GSM to identify the greatest number of scientific journals of Nursing with h index calculated by this bibliometric tool. Bibliographic searches were conducted between 10th and 30th May 2013. #R##N#The result is a ranking of 337 nursing journals sorted by the same h index, and mean as discriminating value. Journals are also grouped by quartiles.

Connected through hyperedge HE-1 (induced by source paper "google scholar as a data source for research assessment"):
  with members:
    - "can we use google scholar to identify highly cited documents"
    - "a two sided academic landscape portrait of highly cited documents in google scholar 1950 2013"
    - "2016 google scholar metrics released a matter of languages and something else"
    - "methods for estimating the size of google scholar"
    - "a new methodology for comparing google scholar and scopus"
    - "google scholar metrics 2014 a low cost bibliometric tool"
    - "does google scholar contain all highly cited documents 1950 2013"
    - "ranking journals could google scholar metrics be an alternative to journal citation reports and scimago journal rank"

Connected through hyperedge HE-2 (induced by source paper "google scholar the big data bibliographic tool"):
  with members:
    - "methods for estimating the size of google scholar"
    - "h index communication journals according to google scholar metrics 2008 2012"
    - "ranking journals could google scholar metrics be an alternative to journal citation reports and scimago journal rank"

Connected through hyperedge HE-3 (induced by source paper "about the size of google scholar playing the numbers"):
  with members:
    - "the silent fading of an academic search engine the case of microsoft academic search"
    - "google scholar metrics evolution an analysis according to languages"

Connected through hyperedge HE-4 (induced by source paper "h index communication journals according to google scholar metrics 2008 2012"):
  with members:
    - "ranking journals could google scholar metrics be an alternative to journal citation reports and scimago journal rank"
    - "manipulating google scholar citations and google scholar metrics simple easy and tempting"

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)