期刊名称：International Journal of Mathematics and Mathematical Sciences
印刷版ISSN：0161-1712
电子版ISSN：1687-0425
出版年度：1992
卷号：15
DOI：10.1155/S0161171292000875
出版社：Hindawi Publishing Corporation
摘要：The following theorem is proved and several fixed point theorems and coincidence theorems are derived as corollaries. Let C be a nonempty convex subset of a normed linear space X, f:C→X a continuous function, g:C→C continuous, onto and almost quasi-convex. Assume that C has a nonempty compact convex subset D such that the setA={y∈C:‖g(x)−f(y)‖≥‖g(y)−f(y)‖   for   all   x∈D}is compact.
