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: "theorema 2 0 a graphical user interface for a mathematical assistant system"
  Abstract: Theorema2.0stands fora re-designincludinga completere-implementationofthe Theoremasystem,which was originallydesigned, developed,and implementedby Bruno Buchbergerand his Theoremagroup at RISC. In this paper, we present the ﬁrst prototype of a graphical user interface (GUI) forthe new system. It heavily relies on powerful interactive capabilities introduced in recent releasesof the underlying Mathematica system, most importantly the possibility of having dynamic objectsconnected to interface elements like sliders, menus, check-boxes, radio-buttons and the like. Allthese features are fully integrated into the Mathematica programming environment and allow theimplementation of a modern user interface.

Connected through hyperedge HE-1 (induced by source paper "advanced proof viewing in prooftool"):
  with members:
    - "ceres for first order schemata"
    - "prooftool a gui for the gapt framework"

Connected through hyperedge HE-2 (induced by source paper "a qualitative comparison of the suitability of four theorem provers for basic auction theory"):
  with members:
    - "the formare project formal mathematical reasoning in economics"
    - "isabelle jedit a prover ide within the pide framework"
    - "automated search for impossibility theorems in social choice theory ranking sets of objects"

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.MS(Mathematical Software)