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: "adore a modular standards based digital object repository"
  Abstract: This paper describes the aDORe repository architecture, designed and implemented for ingesting, storing, and accessing a vast collection of Digital Objects at the Research Library of the Los Alamos National Laboratory. The aDORe architecture is highly modular and standards-based. In the architecture, the MPEG-21 Digital Item Declaration Language is used as the XML-based format to represent Digital Objects that can consist of multiple datastreams as Open Archival Information System Archival Information Packages (OAIS AIPs).Through an ingestion process, these OAIS AIPs are stored in a multitude of autonomous repositories. A Repository Index keeps track of the creation and location of all the autonomous repositories, whereas an Identifier Locator registers in which autonomous repository a given Digital Object or OAIS AIP resides. A front-end to the complete environment, the OAI-PMH Federator, is introduced for requesting OAIS Dissemination Information Packages (OAIS DIPs). These OAIS DIPs can be the stored OAIS AIPs themselves, or transformations thereof. This front-end allows OAI-PMH harvesters to recurrently and selectively collect batches of OAIS DIPs from aDORe, and hence to create multiple, parallel services using the collected objects. Another front-end, the OpenURL Resolver, is introduced for requesting OAIS Result Sets. An OAIS Result Set is a dissemination of an individual Digital Object or of its constituent datastreams. Both front-ends make use of an MPEG-21 Digital Item Processing Engine to apply services to OAIS AIPs, Digital Objects, or constituent datastreams that were specified in a dissemination request.

Connected through hyperedge HE-1 (induced by source paper "when should i make preservation copies of myself"):
  with members:
    - "resurrecting my revolution using social link neighborhood in bringing context to the disappearing web"
    - "the mellon fedora project digital library architecture meets xml and web services"
    - "http mailbox asynchronous restful communication"
    - "analysis of graphs for digital preservation suitability"
    - "from random graph to small world by wandering"
    - "object re use exchange a resource centric approach"
    - "requirements for digital preservation systems a bottom up approach"

Connected through hyperedge HE-2 (induced by source paper "the adore federation architecture"):
  with members:
    - "pathways augmenting interoperability across scholarly repositories"
    - "representing digital assets using mpeg 21 digital item declaration"
    - "fedora an architecture for complex objects and their relationships"
    - "file based storage of digital objects and constituent datastreams xmltapes and internet archive arc files"

Connected through hyperedge HE-3 (induced by source paper "fedora an architecture for complex objects and their relationships"):
  with members:
    - "flexible and extensible digital object and repository architecture fedora"
    - "policy carrying policy enforcing digital objects"
    - "the mellon fedora project digital library architecture meets xml and web services"
    - "an information network overlay architecture for the nsdl"

Connected through hyperedge HE-4 (induced by source paper "access interfaces for open archival information systems based on the oai pmh and the openurl framework for context sensitive services"):
  with members:
    - "flexible and extensible digital object and repository architecture fedora"

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)