@article{10_1017_S0017089500003566,
     author = {Choo, Koo-Guan},
     title = {Whitehead groups of semidirect products of free groups},
     journal = {Glasgow mathematical journal},
     pages = {155--158},
     year = {1978},
     volume = {19},
     number = {2},
     doi = {10.1017/S0017089500003566},
     url = {http://geodesic.mathdoc.fr/articles/10.1017/S0017089500003566/}
}