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 "verification for timed automata extended with unbounded discrete data structures"):
  Abstract: We study decidability of verification problems for timed automata extended#N#with unbounded discrete data structures. More detailed, we extend timed#N#automata with a pushdown stack. In this way, we obtain a strong model that may#N#for instance be used to model real-time programs with procedure calls. It is#N#long known that the reachability problem for this model is decidable. The goal#N#of this paper is to identify subclasses of timed pushdown automata for which#N#the language inclusion problem and related problems are decidable.

Includes members:
  Member "simulation over one counter nets is pspace complete":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "simulation problems over one counter nets")
  Member "reachability games on extended vector addition systems with states":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "energy mean payoff games")

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)