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 "investigating storage as a service cloud platform pcloud as a case study"):
  Abstract: Due to the flexibility, affordability and portability of cloud storage, individuals and companies envisage the cloud storage as one of the preferred storage media nowadays. This attracts the eyes of cyber criminals, since much valuable informa- tion such as user credentials, and private customer records are stored in the cloud. There are many ways for criminals to compromise cloud services; ranging from non-technical attack methods, such as social engineering, to deploying advanced malwares. Therefore, it is vital for cyber forensics examiners to be equipped and informed about best methods for investigation of different cloud platforms. In this chapter, using pCloud (an extensively used online cloud storage service) as a case study, and we elaborate on different kinds of artefacts retrievable during a forensics examination. We carried out our experiments on four different virtual machines running four popular operating systems: a 64 bit Windows 8, Ubuntu 14.04.1 LTS, Android 4.4.2, and iOS 8.1. Moreover, we examined cloud remnants of two different web browsers: Internet Explorer and Google Chrome on Windows. We believe that our study would promote awareness among digital forensic examiners on how to conduct cloud storage forensics examination.

Includes members:
  Member "ubuntu one investigation detecting evidences on client machines":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "forensic investigation of p2p cloud storage bittorrent sync as a case study")
  Member "digital forensic investigation of cloud storage services":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "greening cloud enabled big data storage forensics syncany as a case study")
  Member "cloud storage forensic hubic as a case study":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "greening cloud enabled big data storage forensics syncany as a case study")
  Member "mobile cloud forensics an analysis of seven popular android apps":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "ubuntu one investigation detecting evidences on client machines")
  Member "bittorrent sync first impressions and digital forensic implications":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "greening cloud enabled big data storage forensics syncany as a case study")
  Member "using smartphones as a proxy for forensic evidence contained in cloud storage services":
    also connected through other hyperedges:
      - Hyperedge HE-6 (induced by source paper "a bleeding digital heart identifying residual data generation from smartphone applications interacting with medical devices")

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.CR(Cryptography and Security)