@article{GDZPPN002291401,
title = {Fourth Order Singular Differential Equations.},
journal = {Mathematische Annalen},
volume = {152},
year = {1963},
pages = {320-340},
zbl = {0111.08501},
url = {http://dml.mathdoc.fr/item/GDZPPN002291401}
}
EVERITT, W.N. Fourth Order Singular Differential Equations.. Mathematische Annalen, Tome 152 (1963) pp. 320-340. http://gdmltest.u-ga.fr/item/GDZPPN002291401/