@article{GDZPPN002204568,
title = {A generalization of Mahler's classification to several variables.},
journal = {Journal f\"ur die reine und angewandte Mathematik},
volume = {374},
year = {1987},
pages = {113-126},
zbl = {0614.10031},
url = {http://dml.mathdoc.fr/item/GDZPPN002204568}
}
Yu, Kunrui. A generalization of Mahler's classification to several variables.. Journal für die reine und angewandte Mathematik, Tome 374 (1987) pp. 113-126. http://gdmltest.u-ga.fr/item/GDZPPN002204568/