The existence of continuous selections is proved for a class of lower semicontinuous multifunctions whose values are closed convex subsets of a complete metric space equipped with an appropriate notion of convexity. The approach is based on the notion of pseudo-barycenter of an ordered n-tuple of points.
@article{bwmeta1.element.bwnjournal-article-doi-10_4064-ba52-3-10, author = {F. S. De Blasi and G. Pianigiani}, title = {Continuous Selections in $\alpha$-Convex Metric Spaces}, journal = {Bulletin of the Polish Academy of Sciences. Mathematics}, volume = {52}, year = {2004}, pages = {303-317}, zbl = {1101.54022}, language = {en}, url = {http://dml.mathdoc.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ba52-3-10} }
F. S. De Blasi; G. Pianigiani. Continuous Selections in α-Convex Metric Spaces. Bulletin of the Polish Academy of Sciences. Mathematics, Tome 52 (2004) pp. 303-317. http://gdmltest.u-ga.fr/item/bwmeta1.element.bwnjournal-article-doi-10_4064-ba52-3-10/