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 "quantified ctl expressiveness and complexity"):
  Abstract: While it was defined long ago, the extension of CTL with quantification over#N#atomic propositions has never been studied extensively. Considering two#N#different semantics (depending whether propositional quantification refers to#N#the Kripke structure or to its unwinding tree), we study its expressiveness#N#(showing in particular that QCTL coincides with Monadic Second-Order Logic for#N#both semantics) and characterise the complexity of its model-checking and#N#satisfiability problems, depending on the number of nested propositional#N#quantifiers (showing that the structure semantics populates the polynomial#N#hierarchy while the tree semantics populates the exponential hierarchy).

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 "robust vacuity for branching temporal logic":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "efficient generation of inductive validity cores for safety properties")

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)