We give an example of an extremally disconnected compact Hausdorff space with an open continuous selfmap such that the fixed point set is nonvoid and nowhere dense, resp\. that there is exactly one nonisolated fixed point.
@article{118720, author = {Egbert Th\"ummel}, title = {The fixed point set of open mappings on extremally disconnected spaces}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {35}, year = {1994}, pages = {789-794}, zbl = {0854.54035}, mrnumber = {1321249}, language = {en}, url = {http://dml.mathdoc.fr/item/118720} }
Thümmel, Egbert. The fixed point set of open mappings on extremally disconnected spaces. Commentationes Mathematicae Universitatis Carolinae, Tome 35 (1994) pp. 789-794. http://gdmltest.u-ga.fr/item/118720/
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