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 "syntactic structures of regular languages"):
  Abstract: We introduce here the notion of syntactic lattice algebra which is an analogy of the syntactic monoid and of the syntactic semiring. We present a unified approach to get those three structures.

Includes members:
  Member "one eilenberg theorem to rule them all":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "visibly pushdown languages and free profinite algebras")
  Member "eilenberg theorems for free":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "automata learning an algebraic approach")
  Member "recognisable languages over monads":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "extensions of omega regular languages")
  Member "varieties of languages in a category":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "one eilenberg theorem to rule them all")
  Member "profinite monads profinite equations and reiterman s theorem":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "equational axiomatization of algebras with structure")
  Member "generalized eilenberg theorem i local varieties of languages":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "varieties of data languages")
  Member "on varieties of automata enriched with an algebraic structure extended abstract":
    also connected through other hyperedges:
      (none)
  Member "proceedings 14th international conference on automata and formal languages":
    also connected through other hyperedges:
      (none)

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.FL(Formal Languages and Automata Theory)