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 "branching bisimilarity on normed bpa is exptime complete"):
  Abstract: We put forward an exponential-time algorithm for deciding branching bisimilarity on normed BPA (Bacis Process Algebra) systems. The decidability of branching (or weak) bisimilarity on normed BPA was once a long standing open problem which was closed by Yuxi Fu. The EXPTIME-hardness is an inference of a slight modification of the reduction presented by Richard Mayr. Our result claims that this problem is EXPTIME-complete.

Includes members:
  Member "dividing line between decidable pda s and undecidable ones":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "bisimulation equivalence of first order grammars")
  Member "a polynomial time algorithm for deciding branching bisimilarity on totally normed bpa":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "branching bisimilarity of normed bpa processes as a rational monoid")
  Member "branching bisimilarity of normed bpa processes is in nexptime":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "branching bisimilarity of normed bpa processes as a rational monoid")
  Member "branching bisimilarity checking for prs":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "bisimulation equivalence of first order grammars is ackermann complete")
  Member "bisimilarity on basic process algebra is in 2 exptime an explicit proof":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "branching bisimilarity of normed bpa processes as a rational monoid")
  Member "bpa bisimilarity is exptime hard":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "bisimulation equivalence of first order grammars is ackermann complete")
  Member "equivalence checking on infinite state systems techniques and results":
    also connected through other hyperedges:
      - Hyperedge HE-7 (induced by source paper "simulation problems over one counter nets")

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.LO(Logic in Computer Science)