@article{1077477505,
author = {Berkovitz, Leonard D.},
title = {Double Sturm-Liouville expansions},
journal = {Duke Math. J.},
volume = {19},
number = {1},
year = {1952},
pages = { 567-574},
language = {en},
url = {http://dml.mathdoc.fr/item/1077477505}
}
Berkovitz, Leonard D. Double Sturm-Liouville expansions. Duke Math. J., Tome 19 (1952) no. 1, pp. 567-574. http://gdmltest.u-ga.fr/item/1077477505/