@article{10_21136_CPM_1980_118043,
     author = {Ajmal, Naseem},
     title = {Groupoids with a closure condition},
     journal = {\v{C}asopis pro p\v{e}stov\'an{\'\i} matematiky},
     pages = {14--22},
     publisher = {mathdoc},
     volume = {105},
     number = {1},
     year = {1980},
     doi = {10.21136/CPM.1980.118043},
     mrnumber = {560754},
     zbl = {0447.20042},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CPM.1980.118043/}
}