@article{GDZPPN001251171, title = {An algebraic proof of Isbell' s zigzag theorem.}, journal = {Semigroup forum}, volume = {12}, year = {1976}, pages = {83-88}, zbl = {0325.20064}, url = {http://dml.mathdoc.fr/item/GDZPPN001251171} }
Storrer, H. An algebraic proof of Isbell' s zigzag theorem.. Semigroup forum, Tome 12 (1976) pp. 83-88. http://gdmltest.u-ga.fr/item/GDZPPN001251171/