@article{MZ_1981__178_173085,
     author = {Donald J. Collins and Ian M. Chiswell},
     title = {Aspherical {Group} {Presentations.}},
     journal = {Mathematische Zeitschrift},
     pages = {1--36},
     publisher = {mathdoc},
     volume = {178},
     year = {1981},
     zbl = {0443.20030},
     url = {http://geodesic.mathdoc.fr/item/MZ_1981__178_173085/}
}