@article{GDZPPN002285738, title = {The Riccati Equation: Initial Values and Inequalities.}, journal = {Mathematische Annalen}, volume = {133}, year = {1957}, pages = {235-250}, zbl = {0102.07201}, url = {http://dml.mathdoc.fr/item/GDZPPN002285738} }
Redheffer, R.M. The Riccati Equation: Initial Values and Inequalities.. Mathematische Annalen, Tome 133 (1957) pp. 235-250. http://gdmltest.u-ga.fr/item/GDZPPN002285738/