@misc{Piwowar_Anna_Differential, author={Piwowar, Anna and Walczak, Janusz}, howpublished={online}, language={eng}, abstract={This article is limited to analysis of a system with feedback composed of the first order parametric sections. The differential equation describing the LTV system with feedback has been carried out.}, title={Differential equation of an LTV system with feedback}, keywords={LTV system, feetback connection}, }