@article{01557043,
title = {Product of integers in an interval, modulo squares.},
journal = {The Electronic Journal of Combinatorics [electronic only]},
volume = {DS10},
year = {2002},
zbl = {1107.11042},
language = {en},
url = {http://dml.mathdoc.fr/item/01557043}
}
Granville, Andrew; Selfridge, J. L. Product of integers in an interval, modulo squares.. The Electronic Journal of Combinatorics [electronic only], Tome DS10 (2002) . http://gdmltest.u-ga.fr/item/01557043/