human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "foundational extensible corecursion"):
  Abstract: This paper presents a formalized framework for defining corecursive functions safely in a total setting, based on corecursion up-to and relational parametricity. The end product is a general corecursor that allows corecursive (and even recursive) calls under wellbehaved operations, including constructors. Corecursive functions that are well behaved can be registered as such, thereby increasing the corecursor’s expressiveness. The metatheory is formalized in the Isabelle proof assistant and forms the core of a prototype tool. The corecursor is derived from first principles, without requiring new axioms or extensions of the logic.

Includes members:
  Member "programming and reasoning with guarded recursion for coinductive types":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "the size change principle for mixed inductive and coinductive types")
  Member "co recursion in logic programming lazy vs eager":
    also connected through other hyperedges:
      (none)
  Member "abstract gsos rules and a modular treatment of recursive definitions":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "companions causality and codensity")
  Member "parametricity in an impredicative sort":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "a formal proof of the irrationality of ζ 3")
  Member "miniagda integrating sized and dependent types":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "a type and scope safe universe of syntaxes with binding their semantics and proofs")
  Member "a formally verified compiler back end":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "a survey on theorem provers in formal methods")
  Member "set theory for verification i from foundations to functions":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "formalization of the fundamental group in untyped set theory using auto2")
  Member "set theory for verification ii induction and recursion":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "mutual coinduction")

Question: Please tell me which class the source paper 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.PL(Programming Languages)