2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/140278Most of the examples of wavelet sets are for dilation sets which are groups. We find a necessary and sufficient condition under which subspace wavelet sets exist for dilation sets of the form $A B$, which are not necessarily groups. We explain the construction by a few examples.Has been published in Contemporary MathematicsFunctional Analysis42C40,43A85text