@article{MS2_1957__5_165661,
     author = {BJARNI J\'ONSSON},
     title = {On isomorphism types of groups and other algebraic systems},
     journal = {Mathematica Scandinavica},
     pages = {224--229},
     publisher = {mathdoc},
     volume = {5},
     year = {1957},
     zbl = {0081.26201},
     url = {http://geodesic.mathdoc.fr/item/MS2_1957__5_165661/}
}