@article{MZ_1961__75_169920,
     author = {L.G. Kov\'acs},
     title = {Groups with regular automorphisms of order four.},
     journal = {Mathematische Zeitschrift},
     pages = {277--294},
     publisher = {mathdoc},
     volume = {75},
     year = {1961},
     zbl = {0097.01202},
     url = {http://geodesic.mathdoc.fr/item/MZ_1961__75_169920/}
}