@article{1077475208,
author = {Gottlieb, Morris J.},
title = {Oscillation theorems for self-adjoint boundary value problems},
journal = {Duke Math. J.},
volume = {15},
number = {1},
year = {1948},
pages = { 1073-1091},
language = {en},
url = {http://dml.mathdoc.fr/item/1077475208}
}
Gottlieb, Morris J. Oscillation theorems for self-adjoint boundary value problems. Duke Math. J., Tome 15 (1948) no. 1, pp. 1073-1091. http://gdmltest.u-ga.fr/item/1077475208/