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: "google scholar metrics 2014 a low cost bibliometric tool"
  Abstract: We analyse the main features of the third edition of Google Scholar Metrics (GSM), released in June 2014, focusing on its more important changes, strengths, and weaknesses. Additionally, we present some figures that outline the dimensions of this new edition, and we compare them to those of previous editions. Principal among these figures are the number of visualized publications, publication types, languages, and the maximum and minimum h5-index and h5-median values by language, subject area, and subcategory. This new edition is marked by continuity. There is nothing new other than the updating of the time frame (2009-2013) and the removal of some redundant subcategories (from 268 to 261) for English written publications. Google has just updated the data, which means that some of the errors discussed in previous studies still persist. To sum up, GSM is a minimalist information product with few features, closed (it cannot be customized by the user), and simple (navigating it only takes a few clicks). For these reasons, we consider it a 'low cost' bibliometric tool, and propose a list of features it should incorporate in order to stop being labeled as such. Notwithstanding the above, this product presents a stability in its bibliometric indicators that supports its ability to measure and track the impact of scientific publications.

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"
    - "does google scholar contain all highly cited documents 1950 2013"
    - "h index of scientific nursing journals according to google scholar metrics 2007 2011"
    - "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 "implementing recommendation algorithms in a large scale biomedical science knowledge base"):
  with members:
    - "manipulating google scholar citations and google scholar metrics simple easy and tempting"

Connected through hyperedge HE-3 (induced by source paper "2016 google scholar metrics released a matter of languages and something else"):
  with members:
    - "google scholar metrics 2013 nothing new under the sun"

Connected through hyperedge HE-4 (induced by source paper "does google scholar contain all highly cited documents 1950 2013"):
  with members:
    - "about the size of google scholar playing the numbers"
    - "ranking journals could google scholar metrics be an alternative to journal citation reports and scimago journal rank"
    - "the new excellence indicator in the world report of the scimago institutions rankings 2011"

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)