@article {482, title = {Homotopy Continuation for Spatial Interference Alignment in Arbitrary MIMO X Networks}, journal = {IEEE Transactions on Signal Processing}, volume = {65}, year = {2017}, month = {April}, pages = {1752-1764}, issn = {1053-587X}, doi = {10.1109/TSP.2016.2637310}, author = {Fanjul, Jacobo and Gonz{\'a}lez, {\'O}scar and Santamar{\'\i}a, Ignacio and Beltr{\'a}n, Carlos} }