Seyed Saeed Changiz Rezaei Shahab Oveis Gharan Amir K. Khandani Cooperative Strategies for the Half-Duplex Gaussian Parallel Relay Channel: Simultaneous Relaying versus Successive Relaying http://arxiv.org/abs/0810.4657 2008 CoRR abs/0810.4657 db/journals/corr/corr0810.html#abs-0810-4657