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 "why we engage in floss answers from core developers"):
  Abstract: The maintenance and evolution of Free/Libre Open Source Software (FLOSS) projects demand the constant attraction of core developers. In this paper, we report the results of a survey with 52 developers, who recently became core contributors of popular GitHub projects. We reveal their motivations to assume a key role in FLOSS projects (e.g., improving the projects because they are also using it), the project characteristics that most helped in their engagement process (e.g., a friendly community), and the barriers faced by the surveyed core developers (e.g., lack of time of the project leaders). We also compare our results with related studies about others kinds of open source contributors (casual, one-time, and newcomers).

Includes members:
  Member "why and how java developers break apis":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "interactive effort aware library version harmonization")
  Member "towards an interdisciplinary socio technical analysis of software ecosystem health":
    also connected through other hyperedges:
      (none)
  Member "why modern open source projects fail":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "is this github project maintained measuring the level of maintenance activity of open source projects")
  Member "a novel approach for estimating truck factors":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "refactoring graphs assessing refactoring over time")
  Member "classifying developers into core and peripheral an empirical study on count and network metrics":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "a systematic mapping study of developer social network research")
  Member "understanding the factors that impact the popularity of github repositories":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "is this github project maintained measuring the level of maintenance activity of open source projects")
  Member "why we refactor confessions of github contributors":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "refactoring graphs assessing refactoring over time")

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.SE(Software Engineering)