@article{GDZPPN002092077,
title = {Differentiable Group Actions on Homotopy Spheres. I. Differential Structure and the Knot Invariant.},
journal = {Inventiones mathematicae},
volume = {34},
year = {1976},
pages = {105-128},
zbl = {0335.57025},
url = {http://dml.mathdoc.fr/item/GDZPPN002092077}
}
Schultz, Reinhard. Differentiable Group Actions on Homotopy Spheres. I. Differential Structure and the Knot Invariant.. Inventiones mathematicae, Tome 34 (1976) pp. 105-128. http://gdmltest.u-ga.fr/item/GDZPPN002092077/