Voir la notice de l'article provenant de la source Czech Digital Mathematics Library
@article{MASLO_1978__28_1_a0, author = {\v{S}ipo\v{s}, J\'an}, title = {Subalgebras and sublogics of $\sigma$-logics}, journal = {Mathematica slovaca}, pages = {3--9}, publisher = {mathdoc}, volume = {28}, number = {1}, year = {1978}, mrnumber = {527769}, zbl = {0365.02015}, language = {en}, url = {http://geodesic.mathdoc.fr/item/MASLO_1978__28_1_a0/} }
Šipoš, Ján. Subalgebras and sublogics of $\sigma$-logics. Mathematica slovaca, Tome 28 (1978) no. 1, pp. 3-9. http://geodesic.mathdoc.fr/item/MASLO_1978__28_1_a0/