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: "a distribution law for ccs and a new congruence result for the p calculus"
  Abstract: We give an axiomatisation of strong bisimilarity on a small fragment of CCS#N#that does not feature the sum operator. This axiomatisation is then used to#N#derive congruence of strong bisimilarity in the finite pi-calculus in absence#N#of sum. To our knowledge, this is the only nontrivial subcalculus of the#N#pi-calculus that includes the full output prefix and for which strong#N#bisimilarity is a congruence.

Connected through hyperedge HE-1 (induced by source paper "unique parallel decomposition for the π calculus"):
  with members:
    - "unique parallel decomposition in branching and weak bisimulation semantics"
    - "a finite equational base for ccs with left merge and communication merge"

Connected through hyperedge HE-2 (induced by source paper "unique parallel decomposition in branching and weak bisimulation semantics"):
  with members:
    - "a geometric approach to the problem of unique decomposition of processes"
    - "a finite equational base for ccs with left merge and communication merge"

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)