human: Given a node-centered hypergraph: <hypergraph>, where nodes represent papers and hyperedges represent sets of papers co-cited by a source paper.

Details of the hypergraph:
Center node: "monadic second order definable graph orderings"
  Abstract: We study the question of whether, for a given class of finite graphs, one can#N#define, for each graph of the class, a linear ordering in monadic second-order#N#logic, possibly with the help of monadic parameters. We consider two variants#N#of monadic second-order logic: one where we can only quantify over sets of#N#vertices and one where we can also quantify over sets of edges. For several#N#special cases, we present combinatorial characterisations of when such a linear#N#ordering is definable. In some cases, for instance for graph classes that omit#N#a fixed graph as a minor, the presented conditions are necessary and#N#sufficient; in other cases, they are only necessary. Other graph classes we#N#consider include complete bipartite graphs, split graphs, chordal graphs, and#N#cographs. We prove that orderability is decidable for the so called#N#HR-equational classes of graphs, which are described by equation systems and#N#generalize the context-free languages.

Connected through hyperedge HE-1 (induced by source paper "timed systems through the lens of logic"):
  with members:
    - "non sequential theory of distributed systems"
    - "decidability of timed communicating automata"
    - "binary reachability of timed pushdown automata via quantifier elimination and cyclic order atoms"
    - "towards an efficient tree automata based technique for timed systems"
    - "analyzing timed systems using tree automata"
    - "timed pushdown automata revisited"
    - "quantified ctl expressiveness and complexity"

Connected through hyperedge HE-2 (induced by source paper "order invariance on decomposable structures"):
  with members:
    - "definability equals recognizability for graphs of bounded treewidth"
    - "canonizing graphs of bounded tree width in logspace"
    - "fixed parameter tractable canonization and isomorphism test for graphs of bounded treewidth"
    - "order invariant mso is stronger than counting mso in the finite"

Question: Please tell me which class the center node 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)