@article{IM_1986__86_143410,
     author = {M.V. Pimsner},
     title = {Of-groups of crossed products by groups acting on trees.},
     journal = {Inventiones mathematicae},
     pages = {603--634},
     publisher = {mathdoc},
     volume = {86},
     year = {1986},
     zbl = {0638.46049},
     url = {http://geodesic.mathdoc.fr/item/IM_1986__86_143410/}
}