@article{1077468062,
author = {Wintner, Aurel},
title = {A comparison theorem for Sturmian oscillation numbers of
linear systems of second order},
journal = {Duke Math. J.},
volume = {25},
number = {1},
year = {1958},
pages = { 515-518},
language = {en},
url = {http://dml.mathdoc.fr/item/1077468062}
}
Wintner, Aurel. A comparison theorem for Sturmian oscillation numbers of
linear systems of second order. Duke Math. J., Tome 25 (1958) no. 1, pp. 515-518. http://gdmltest.u-ga.fr/item/1077468062/