Inverse source non-local problem for mixed type equation with Caputo   fractional differential operator
  In the present work, we discuss a unique solvability of an inverse-source problem with integral transmitting condition for time-fractional mixed type equation in a rectangular domain, where the unknown source term depends on space variable only.   The method of solution based on a series expansion using bi-orthogonal basis of space corresponding to a nonself-adjoint boundary value problem. Under certain regularity conditions on the given data, we prove the uniqueness and existence of the solution for the given problem. Influence of transmitting condition on the solvability of the problem is shown as well. Precisely, two different cases were considered; a case of full integral form ($0<\gamma<1$) and a special case ($\gamma=1$) of transmitting condition.   In order to simplify the bulky expressions appearing in the proof of the main result, we have established a new property of the recently introduced Mittag-Leffler type function of two variables (see Lemma 2.1). 
Erkinjon Karimov, Nasser Al-Salti, and Sebti Kerbal
math.AP