@article{article3b717718,
title   = {A Hopf-Galois correspondence for free algebras},
author = {Ferreira, Vitor de Oliveira and Murakami, Lúcia Satie Ikemoto and Paques, Antonio},
year = {2004},
doi = {10.1016/s0021-8693(03)00502-7},
journal   = {Journal of Algebra}
}