Belmonte Beitia, Juan. Pérez García, Victor M.. 

Using similarity transformations we construct explicit nontrivial solutions of nonlinear Schr¨odinger equations with potentials and nonlinearities depending on time and on the spatial coordinates. We present the general theory and use it to calculate explicitly non-trivial solutions such as periodic (breathers), resonant or quasiperiodically oscillating solitons. Some implications to the field of matter-waves are also discussed.