@article{10_21136_CMJ_1980_101663,
     author = {Schwarz, \v{S}tefan},
     title = {The {Euler-Fermat} theorem for the semigroup of circulant {Boolean} matrices},
     journal = {Czechoslovak Mathematical Journal},
     pages = {135--141},
     publisher = {mathdoc},
     volume = {30},
     number = {1},
     year = {1980},
     doi = {10.21136/CMJ.1980.101663},
     mrnumber = {565916},
     zbl = {0443.20053},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1980.101663/}
}