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: "on projections of arbitrary lattices"
  Abstract: In this paper we prove that given any two point lattices Λ1⊂Rn and Λ2⊂Rn−k, there is a set of k vectors {v1,…,vk}⊂Λ1 such that Λ2 is, up to similarity, arbitrarily close to the projection of Λ1 onto the orthogonal complement of the subspace spanned by {v1,…,vk}. This result extends the main theorem of Sloane et al. (2011) [1] and has applications in communication theory.

Connected through hyperedge HE-1 (induced by source paper "well rounded lattices via polynomials"):
  with members:
    - "well rounded lattices for coset coding in mimo wiretap channels"
    - "well rounded lattices for reliability and security in rayleigh fading siso channels"

Connected through hyperedge HE-2 (induced by source paper "a note on subortogonal lattices"):
  with members:
    - "optimum commutative group codes"

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.CG(Computational Geometry)