@article{MZ_1968__104_170932,
     author = {M.J. Dunwoody},
     title = {On {Product} {Varieties.}},
     journal = {Mathematische Zeitschrift},
     pages = {91--97},
     publisher = {mathdoc},
     volume = {104},
     year = {1968},
     zbl = {0155.04501},
     url = {http://geodesic.mathdoc.fr/item/MZ_1968__104_170932/}
}