@article{10_21136_CMJ_1981_101736,
     author = {Hardy, D. and Pastijn, Francis J.},
     title = {The maximal regular ideal of the semigroup of binary relations},
     journal = {Czechoslovak Mathematical Journal},
     pages = {194--198},
     publisher = {mathdoc},
     volume = {31},
     number = {2},
     year = {1981},
     doi = {10.21136/CMJ.1981.101736},
     mrnumber = {611074},
     zbl = {0467.20049},
     language = {en},
     url = {https://geodesic-test.mathdoc.fr/articles/10.21136/CMJ.1981.101736/}
}