“…To our knowledge, the first result concerning the evolution problem belongs to Lei, Lin, and Zhou [15], who showed that the 2+1-dimensional system (2) is globally well-posed for smooth, compactly-supported initial data with small H 11 (R 2 ) norm. This was followed by work of Geba, Nakanishi, and Zhang [12] in the equivariant case, which consists of global well-posedness and scattering for(4), with N 1 = 0 and initial data having a small Besov-Sobolev norm at the level of H 2 (R 2 ).…”