Non-Debye Relaxations: Two Types of Memories and Their Stieltjes Character

We show that spectral functions relevant for commonly used models of the non-Debye relaxation are related to Stieltjes supported on positive semiaxis. Using only this property it can be shown response and nonnegative. They connected each other obey time evolution provided by integral equations involving memory function $M(t)$ which is as well. This fact also due character function. Stochastic processes based approach phenomena gives possibility identify with Laplace (L\'evy) exponent some infinitely divisible stochastic process introduce its partner $k(t)$. Both memories Sonine equation lead equivalent may freely interchanged in dependence our knowledge governing process.