@article{MZ_1967__102_170871,
     author = {Narain D. Gupta and Se\'an J. Tobin},
     title = {On {Certain} {Groups} with {Exponent} {Four.}},
     journal = {Mathematische Zeitschrift},
     pages = {216--226},
     publisher = {mathdoc},
     volume = {102},
     year = {1967},
     zbl = {0157.35001},
     url = {http://geodesic.mathdoc.fr/item/MZ_1967__102_170871/}
}