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 "an algebra of actors based on true concurrency"):
  Abstract: An algebra of actors $\textrm{A}\pi$ fully captures the properties of actors based on asynchronous $\pi$-calculus, but, it is based on the interleaving bisimulation semantics. We adjust $\textrm{A}\pi$ to $\textrm{A}\pi_{tc}$ to make $\textrm{A}\pi$ having a truly concurrent semantics. We give the syntax and operational semantics of $\textrm{A}\pi_{tc}$, and also the truly concurrent semantics model and algebraic laws of $\textrm{A}\pi_{tc}$.

Includes members:
  Member "a calculus for true concurrency":
    also connected through other hyperedges:
      (none)
  Member "algebraic laws for true concurrency":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "truly concurrent bisimilarities are game equivalent")
  Member "weakly true concurrency and its logic":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "a calculus for true concurrency")
  Member "a logic for true concurrency":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "conflict vs causality in event structures")
  Member "a logic with reverse modalities for history preserving bisimulations":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "a calculus for true concurrency")

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)