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 "bisimulation equivalence of first order grammars is ackermann hard"):
  Abstract: Bisimulation equivalence (or bisimilarity) of first-order grammars is decidable, as follows from the decidability result by Senizergues (1998, 2005) that has been given in an equivalent framework of equational graphs with finite out-degree, or of pushdown automata (PDA) with only deterministic and popping epsilon-transitions. Benedikt, Goeller, Kiefer, and Murawski (2013) have shown that the bisimilarity problem for PDA (even) without epsilon-transitions is nonelementary. Here we show Ackermann-hardness for bisimilarity of first-order grammars. The grammars do not use explicit epsilon-transitions, but they correspond to the above mentioned PDA with (deterministic and popping) epsilon-transitions, and this feature is substantial in the presented lower-bound proof. The proof is based on a (polynomial) reduction from the reachability problem of reset (or lossy) counter machines, for which the Ackermann-hardness has been shown by Schnoebelen (2010); in fact, this reachability problem is known to be Ackermann-complete in the hierarchy of fast-growing complexity classes defined by Schmitz (2013).

Includes members:
  Member "complexity hierarchies beyond elementary":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "the ideal approach to computing closed subsets in well quasi orderings")
  Member "the bisimulation problem for equational graphs of finite out degree":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "bisimulation equivalence of first order grammars is ackermann complete")

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)