“…Although the vector 0π pulse of self-induced transparency, which is a special type of two-breather molecule, was first noticed for optical nonlinear waves, later, using the generalized perturbative reduction method, the same two-breather molecules were discovered for waves of a different nature described by other nonlinear partial differential equations, such as are the Boussinesq-type equation, the Benjamin-Bona-Mahony equation, and the Hirota equation [7,9,[35][36][37].…”