@article{MASLO_1976_26_1_a1,
     author = {Pastijn, Francis},
     title = {A theorem concerning the restriction of the $\cal D$-structure of a semigroup $S$ to a subsemigroup of $S$},
     journal = {Mathematica slovaca},
     pages = {19--22},
     year = {1976},
     volume = {26},
     number = {1},
     mrnumber = {0427504},
     zbl = {0335.20033},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/MASLO_1976_26_1_a1/}
}