@article{SF_1980__21_134458,
     author = {K.D. jr. Magill and P.R. Misra and U.B. Tewari},
     title = {Unifying congruences on {S(I).}},
     journal = {Semigroup forum},
     pages = {361--372},
     publisher = {mathdoc},
     volume = {21},
     year = {1980},
     zbl = {0456.54030},
     url = {http://geodesic.mathdoc.fr/item/SF_1980__21_134458/}
}