@article{MAN_1970__185_161959,
     author = {A.G.R. STEWART},
     title = {On {Centre-extended-by-metabelian} {Groups.}},
     journal = {Mathematische Annalen},
     pages = {285--302},
     publisher = {mathdoc},
     volume = {185},
     year = {1970},
     zbl = {0176.29703},
     url = {http://geodesic.mathdoc.fr/item/MAN_1970__185_161959/}
}