@article{SF_1981__23_134504,
     author = {P. Goralcik and V. Koubek},
     title = {Inner extrapolation of semigroup translations.},
     journal = {Semigroup forum},
     pages = {73--84},
     publisher = {mathdoc},
     volume = {23},
     year = {1981},
     zbl = {0467.20051},
     url = {http://geodesic.mathdoc.fr/item/SF_1981__23_134504/}
}