@article{ARM_1968__4_1_a1, author = {Sekanina, Milan}, title = {Categories of ordered sets}, journal = {Archivum mathematicum}, pages = {25--59}, publisher = {mathdoc}, volume = {04}, number = {1}, year = {1968}, mrnumber = {0263721}, zbl = {0196.03701}, language = {en}, url = {http://geodesic.mathdoc.fr/item/ARM_1968__4_1_a1/} }