@article{MZ_1970__117_171408,
     author = {James E. Roseblade and Andrew Rae},
     title = {Automorphism {Towers} of {Extremal} {Groups.}},
     journal = {Mathematische Zeitschrift},
     pages = {70--75},
     publisher = {mathdoc},
     volume = {117},
     year = {1970},
     zbl = {0213.30101},
     url = {http://geodesic.mathdoc.fr/item/MZ_1970__117_171408/}
}