@article{10_4171_ggd_109,
     author = {Stephen Majewicz and Marcos Zyman},
     title = {On the extraction of roots in exponential $A$-groups},
     journal = {Groups, geometry, and dynamics},
     pages = {835--846},
     year = {2010},
     volume = {4},
     number = {4},
     doi = {10.4171/ggd/109},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/109/}
}