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: "publishing math lecture notes as linked data"
  Abstract: We mark up a corpus of LaTeX lecture notes semantically and expose them as Linked Data in XHTML+MathML+RDFa. Our application makes the resulting documents interactively browsable for students. Our ontology helps to answer queries from students and lecturers, and paves the path towards an integration of our corpus with external sites.

Connected through hyperedge HE-1 (induced by source paper "the planetary system executable science technology engineering and math papers"):
  with members:
    - "swim a semantic wiki for mathematical knowledge management"
    - "stex a system for flexible formalization of linked data"
    - "dimensions of formality a case study for mkm in software engineering"

Connected through hyperedge HE-2 (induced by source paper "stexide an integrated development environment for stex collections"):
  with members:
    - "stex a system for flexible formalization of linked data"
    - "dimensions of formality a case study for mkm in software engineering"
    - "towards mkm in the large modular representation and scalable software architecture"

Connected through hyperedge HE-3 (induced by source paper "stex a system for flexible formalization of linked data"):
  with members:
    - "stexide an integrated development environment for stex collections"
    - "dimensions of formality a case study for mkm in software engineering"

Connected through hyperedge HE-4 (induced by source paper "editing knowledge in large mathematical corpora a case study with semantic latex stex"):
  with members:
    - "digital mathematics libraries the good the bad the ugly"
    - "towards mkm in the large modular representation and scalable software architecture"

Connected through hyperedge HE-5 (induced by source paper "dimensions of formality a case study for mkm in software engineering"):
  with members:
    - "stex a system for flexible formalization of linked 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)