Analogue of Bitsadze-Samarskiy problem for the loaded equation of the third order with multiple characteristics

This work is devoted to formulation and exploration of non-local boundary problem for loaded equation of mixed type of the third order with multiple characteristics. The singularity of solution is proved by energy integer methods and its existence by transformation of Laplas`s method transferences equivalently to Fredholm`s integer equation of second kind, which has one solution.