@article{GDZPPN002231034, title = {Comparison Theory for Riccati equations.}, journal = {Manuscripta mathematica}, volume = {67}, year = {1990}, pages = {209-214}, zbl = {0714.53029}, url = {http://dml.mathdoc.fr/item/GDZPPN002231034} }
Heintze, E.; Eschenburg, J.-H. Comparison Theory for Riccati equations.. Manuscripta mathematica, Tome 67 (1990) pp. 209-214. http://gdmltest.u-ga.fr/item/GDZPPN002231034/