Separation and the existence theorem for second order nonlinear differential equation

Maximal Regularity Estimate for a Differential Equation With Oscillating Coefficients

“…In this paper, unlike [1] as well as [7], we will assume that the coefficients ρ(x) and r(x) do not follow the weak fluctuation conditions. Such conditions usually appear when evaluating the norm of the higher derivative of a solution to the second-order singular differential equation.…”

Inequalities and Separation for a Biharmonic Laplace-Beltrami Differential Operator in a Hilbert Space Associated with the Existence and Uniqueness Theorem

“…Further results for separation of differential operators can be found in [22][23][24][25][26][27][28][29][30].…”