In this paper, we are introducing certain subfamilies of holomorphic functions and making an attempt to obtain upper bound (UB) the second third order Hankel determinants by applying lemmas, Toeplitz determinants, for normalized analytic belong these classes, defined on open unit disc in complex plane. For one inequality, have obtained sharp bound.

In this paper we solve positive and contractive multiblock problems in the Wiener algebra of almost periodic functions of several variables. We thus generalize the classical four block problem that appears in robust control in many ways. The necessary and sufficient conditions are in terms of appropriate Toeplitz (positive case) and Hankel operators (contractive case) on Besikovitch space. In a...