Maziar SanjabiMeisam RazaviyaynZhi-Quan LuoOptimal joint base station assignment and downlink beamforming for heterogeneous networks.2821-28242012ICASSPhttps://doi.org/10.1109/ICASSP.2012.6288504conf/icassp/2012db/conf/icassp/icassp2012.html#SanjabiRL12