@article{1256048935,
author = {Devinatz, Allen and Friedman, Avner},
title = {The asymptotic behavior of the principal eigenvalue of singularly perturbed degenerate elliptic operators},
journal = {Illinois J. Math.},
volume = {21},
number = {4},
year = {1977},
pages = { 852-870},
language = {en},
url = {http://dml.mathdoc.fr/item/1256048935}
}
Devinatz, Allen; Friedman, Avner. The asymptotic behavior of the principal eigenvalue of singularly perturbed degenerate elliptic operators. Illinois J. Math., Tome 21 (1977) no. 4, pp. 852-870. http://gdmltest.u-ga.fr/item/1256048935/