@article{1250181480,
author = {Lewis, D.W.},
title = {Levels of quaternion algebras},
journal = {Rocky Mountain J. Math.},
volume = {19},
number = {4},
year = {1989},
pages = { 787-792},
language = {en},
url = {http://dml.mathdoc.fr/item/1250181480}
}
Lewis, D.W. Levels of quaternion algebras. Rocky Mountain J. Math., Tome 19 (1989) no. 4, pp. 787-792. http://gdmltest.u-ga.fr/item/1250181480/