Perčinkova-V’čkova, D. Sur une équation différentielle linéaire du second ordre. (Macedonian. French summary) Zbl 0075.07403 Bull. Soc. Math. Phys. Macédoine 6, 27-29 (1956). MSC: 34A30 PDFBibTeX XMLCite \textit{D. Perčinkova-V'čkova}, Bull. Soc. Math. Phys. Macedoine 6, 27--29 (1956; Zbl 0075.07403)
Petropavlovskaja, R. V. On the oscillation of solutions of a differential equation. (Über die Oszillation der Lösungen einer Differentialgleichung.) (Russian) Zbl 0070.08303 Usp. Mat. Nauk 11, No. 4(70), 203-204 (1956). MSC: 34C10 34A34 PDFBibTeX XMLCite \textit{R. V. Petropavlovskaja}, Usp. Mat. Nauk 11, No. 4(70), 203--204 (1956; Zbl 0070.08303) Full Text: MNR