@article{10_4153_CJM_1975_135_6,
     author = {Edmunds, Charles C.},
     title = {Products of {Commutators} as {Products} of {Squares}},
     journal = {Canadian journal of mathematics},
     pages = {1329--1335},
     year = {1975},
     volume = {27},
     number = {6},
     doi = {10.4153/CJM-1975-135-6},
     url = {http://geodesic.mathdoc.fr/articles/10.4153/CJM-1975-135-6/}
}