Lu, X[Lu, Xiao]; Wang, P[Wang, Ping]; Niyato, D[Niyato, Dusit]; Kim, DI[Kim, Dong In]; Han, Z[Han, Zhu]
ArticleIssue Date2015CitationIEEE COMMUNICATIONS SURVEYS AND TUTORIALS, v.17, no.2, pp.757 - 789PublisherIEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC