IEEE Communications Surveys & Tutorials
IEEE Communications Surveys & Tutorials > 2012 > 14 > 1 > 87 - 108
IEEE Communications Surveys & Tutorials > 2012 > 14 > 2 > 311 - 321
IEEE Communications Surveys & Tutorials > 2012 > 14 > 1 > 87 - 108
IEEE Communications Surveys & Tutorials > 2012 > 14 > 2 > 311 - 321