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: "human factors of formal methods"
  Abstract: This paper provides a brief introduction to the work that aims to apply the achievements within the area of engineering psychology to the area of formal methods, focusing on the specification phase of a system development process.

Connected through hyperedge HE-1 (induced by source paper "a domain specific language for verifying software requirement constraints"):
  with members:
    - "cd2alloy class diagrams analysis using alloy revisited"

Connected through hyperedge HE-2 (induced by source paper "focusst solution for analysis of cryptographic properties"):
  with members:
    - "spatio temporal features of focusst"

Connected through hyperedge HE-3 (induced by source paper "towards a human centred approach in modelling and testing of cyber physical systems"):
  with members:
    - "human factors in software reliability engineering"
    - "agile test based modeling"
    - "from abstract modelling to remote cyber physical integration interoperability testing"
    - "cyber virtual systems simulation validation visualization"
    - "towards system development methodologies from software to cyber physical domain"
    - "assumptions underlying agile software development processes"
    - "verified system development with the autofocus tool chain"

Connected through hyperedge HE-4 (induced by source paper "boring formal methods or sherlock holmes deduction methods"):
  with members:
    - "applied logic in engineering"
    - "teaching logic to information systems students challenges and opportunities"
    - "verified system development with the autofocus tool chain"

Connected through hyperedge HE-5 (induced by source paper "spatio temporal features of focusst"):
  with members:
    - "human factors in software reliability engineering"
    - "from abstract modelling to remote cyber physical integration interoperability testing"
    - "cyber virtual systems simulation validation visualization"

Connected through hyperedge HE-6 (induced by source paper "spatio temporal models for formal analysis and property based testing"):
  with members:
    - "an example for bespaced and its use for decision support in industrial automation"
    - "human factors in software reliability engineering"
    - "bespaced towards a tool framework and methodology for the specification and verification of spatial behavior of distributed software component systems"

Connected through hyperedge HE-7 (induced by source paper "model based generation of natural language specifications"):
  with members:
    - "human factors in software reliability engineering"

Connected through hyperedge HE-8 (induced by source paper "human factors in software reliability engineering"):
  with members:
    - "do we really need to write documentation for a system case tool add ons generator editor for a precise documentation"
    - "verified system development with the autofocus tool chain"

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.SE(Software Engineering)