@article{120154, author = {Ji\v r\'\i\ Rach\r unek}, title = {Modal operators on ordered sets}, journal = {Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica}, volume = {24}, year = {1985}, pages = {9-14}, zbl = {0621.06003}, mrnumber = {879015}, language = {en}, url = {http://dml.mathdoc.fr/item/120154} }
Rachůnek, Jiří. Modal operators on ordered sets. Acta Universitatis Palackianae Olomucensis. Facultas Rerum Naturalium. Mathematica, Tome 24 (1985) pp. 9-14. http://gdmltest.u-ga.fr/item/120154/
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