@article{1102779123,
author = {Lewis, Roger T. and Wright, Lynne C.},
title = {Comparison and oscillation criteria for selfadjoint vector-matrix differential equations.},
journal = {Pacific J. Math.},
volume = {91},
number = {2},
year = {1980},
pages = { 125-134},
language = {en},
url = {http://dml.mathdoc.fr/item/1102779123}
}
Lewis, Roger T.; Wright, Lynne C. Comparison and oscillation criteria for selfadjoint vector-matrix differential equations.. Pacific J. Math., Tome 91 (1980) no. 2, pp. 125-134. http://gdmltest.u-ga.fr/item/1102779123/