@article{105067, author = {V\'aclav Havel}, title = {Join systems and closure spaces}, journal = {Commentationes Mathematicae Universitatis Carolinae}, volume = {007}, year = {1966}, pages = {335-341}, zbl = {0146.16105}, mrnumber = {0212650}, language = {en}, url = {http://dml.mathdoc.fr/item/105067} }
Havel, Václav. Join systems and closure spaces. Commentationes Mathematicae Universitatis Carolinae, Tome 007 (1966) pp. 335-341. http://gdmltest.u-ga.fr/item/105067/
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