@article{1256047483,
author = {James, David M.},
title = {Free circle actions on homotopy nine spheres},
journal = {Illinois J. Math.},
volume = {24},
number = {4},
year = {1980},
pages = { 681-688},
language = {en},
url = {http://dml.mathdoc.fr/item/1256047483}
}
James, David M. Free circle actions on homotopy nine spheres. Illinois J. Math., Tome 24 (1980) no. 4, pp. 681-688. http://gdmltest.u-ga.fr/item/1256047483/