Professor Kiguradze's scientific interests cover a wide range of topics belonging to qualitative theory of ordinary and functional-differential equations.
Later, appropriate versions of this method were developed for handling more general types of nonlinear boundary value problems for ordinary and functional-differential equations.
Analogous problems are investigated in [1] [5] (see also the references therein) for the general nonlinear boundary value problems for ordinary differential and functional-differential systems, and in [6] [10] (see also the references therein) for generalized ordinary differential systems.
Topological degree theory can be applied to study the almost periodic nonlinear systems including the ordinary differential equations and functional differential equations.
The theory of boundary value problems for ordinary differential equations and functional differential equations plays an important role in many research fields of science and engineering; for details, see [1 9] and the references therein.
In this paper we show a connection between Levin-Nohel integro-differential equations and ordinary functional differential equations.
The main house is comfortable, yet unspectacular; it looks like a modest ski lodge, airy and filled with light, but the furniture is absolutely ordinary, functional, and the floors are carpeted in plain, almost industrial, colors.
They are also used in the studies of functional equations, ordinary and partial differential equations, integral and integro-differential equations, fractional partial differential equations, and optimal control theory (see [3, 13 23]).
Many papers have been published about the existence analysis of periodic boundary value problems of first and second order for ordinary or functional or integro-differential equations with impulsive.
Many papers have been published about existence analysis of periodic boundary value problems of first and second order for impulsive ordinary or functional or integro-differential equations.
The literature related to ordinary neutral functional differential equations is very extensive and we refer the reader to Chukwu [1], Hale and Lunel [2], Wu [3], and the references therein.
