@article{ARM_1973_9_2_a6,
     author = {Baldri\'an, Ji\v{r}{\'\i}},
     title = {On strong homomorphisms of finitely semigenerated languages},
     journal = {Archivum mathematicum},
     pages = {89--97},
     year = {1973},
     volume = {9},
     number = {2},
     mrnumber = {0356586},
     zbl = {0296.68083},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_1973_9_2_a6/}
}