1. and , Theory of ordinary differential equations, New York, Toronto, London 1955.
2. [Russian Text Ignored] 36 [Russian Text Ignored] 2, 450–471 (1972).
3. Über entartete gewöhnliche Differentialgleichungen
4. Matrizenrechung I, Berlin 1970.
5. φ. XAPTMAH, [Russian Text Ignored] 1970.