@article{01863412,
title = {Maximal index automorphisms of free groups with no attracting fixed points on the boundary are Dehn twists.},
journal = {Geometry \& Topology},
volume = {6},
year = {2002},
pages = {897-919},
doi = {10.2140/agt.2002.2.897},
zbl = {1047.20021},
language = {en},
url = {http://dml.mathdoc.fr/item/01863412}
}
Martino, Armando. Maximal index automorphisms of free groups with no attracting fixed points on the boundary are Dehn twists.. Geometry & Topology, Tome 6 (2002) pp. 897-919. doi : 10.2140/agt.2002.2.897. http://gdmltest.u-ga.fr/item/01863412/