@article{10_4171_ggd_51,
     author = {Matt T. Clay},
     title = {Deformation spaces of $G$-trees and automorphisms of {Baumslag{\textendash}Solitar} groups},
     journal = {Groups, geometry, and dynamics},
     pages = {39--69},
     year = {2009},
     volume = {3},
     number = {1},
     doi = {10.4171/ggd/51},
     url = {http://geodesic.mathdoc.fr/articles/10.4171/ggd/51/}
}