@article{10_4171_ggd_62,
     author = {Andrew J. Duncan and Alina Vdovina},
     title = {Square-free words as products of commutators},
     journal = {Groups, geometry, and dynamics},
     pages = {379--387},
     year = {2009},
     volume = {3},
     number = {3},
     doi = {10.4171/ggd/62},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/62/}
}