@article{CMUC_2009_50_4_a2,
     author = {Kala, V{\'\i}t\v{e}zslav and Kepka, Tom\'a\v{s} and Korbel\'a\v{r}, Miroslav},
     title = {Notes on commutative parasemifields},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {521--533},
     year = {2009},
     volume = {50},
     number = {4},
     mrnumber = {2583130},
     zbl = {1203.16038},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_2009_50_4_a2/}
}