2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/79751Using the dbar-problem and dual dbar-problem, we derive bilinear relations which allows us to construct integrable hierarchies in different parametrizations, their Darboux-Bäcklund transformations and to analyze constraints for them ina very simple way. Scalar KP, BKP and CKP hierarchies are considered as examples.Latex, amsfonts. 12 pagesExactly Solvable and Integrable Systemstext