In this paper we study the existence and uniqueness of positive and periodic solutions of nonlinear delay integral systems of the type $$ x(t) = \int_{t-\tau _1}^t f(s,x(s),y(s))\,ds $$ $$ y(t) = \int_{t-\tau _2}^t g(s,x(s),y(s))\,ds $$ which model population growth in a periodic environment when there is an interaction between two species. For the proofs, we develop an adequate method of sub-supersolutions which provides, in some cases, an iterative scheme converging to the solution.
@article{118705,
author = {Antonio Ca\~nada and Abderrahim Zertiti},
title = {Systems of nonlinear delay integral equations modelling population growth in a periodic environment},
journal = {Commentationes Mathematicae Universitatis Carolinae},
volume = {35},
year = {1994},
pages = {633-644},
zbl = {0816.45002},
mrnumber = {1321234},
language = {en},
url = {http://dml.mathdoc.fr/item/118705}
}
Cañada, Antonio; Zertiti, Abderrahim. Systems of nonlinear delay integral equations modelling population growth in a periodic environment. Commentationes Mathematicae Universitatis Carolinae, Tome 35 (1994) pp. 633-644. http://gdmltest.u-ga.fr/item/118705/
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