@article{GDZPPN002061597,
title = {Commutators of Diffeomorphisms: II.},
journal = {Commentarii mathematici Helvetici},
volume = {50},
year = {1975},
pages = {33-40},
zbl = {0299.58008},
url = {http://dml.mathdoc.fr/item/GDZPPN002061597}
}
Mather, John N. Commutators of Diffeomorphisms: II.. Commentarii mathematici Helvetici, Tome 50 (1975) pp. 33-40. http://gdmltest.u-ga.fr/item/GDZPPN002061597/