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 "towards taming java wildcards and extending java with interval types"):
  Abstract: Of the complex features of generic nominally-typed OO type systems, wildcard types and variance annotations are probably the hardest to fully grasp. As demonstrated when adding closures (a.k.a., lambdas) and when extending type inference in Java, wildcard types and variance annotations make the development and progress of OO programming languages, and of their type systems in particular, a challenging and delicate task. #R##N#In this work we build on our concurrent work, in which we model Java subtyping using a partial graph product, to suggest how wildcard types in Java can be generalized, and simplified, to interval types. In particular, interval types correspond to endpoints of paths in the Java subtyping graph. #R##N#In addition to being a simple and more familiar notion, that is easier to grasp than wildcard types, interval types are strictly more expressive than wildcard types. As such, we believe interval types, when developed and analyzed in full, will be a welcome addition to Java and other similar generic nominally-typed OO programming languages.

Includes members:
  Member "towards an accurate mathematical model of generic nominally typed oop":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "partial cartesian graph product")
  Member "java generics are turing complete":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "behavioural types for memory and method safety in a core object oriented language")

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.PL(Programming Languages)