APA (7th ed.) Citation

Olejnik, O. A., & Radkevič, E. V. (1973). Second order equations with nonnegative characteristic form. American Math. Soc. u.a.

Chicago Style (17th ed.) Citation

Olejnik, Olʹga A., and E. V. Radkevič. Second Order Equations with Nonnegative Characteristic Form. Providence, RI u.a: American Math. Soc. u.a, 1973.

MLA (9th ed.) Citation

Olejnik, Olʹga A., and E. V. Radkevič. Second Order Equations with Nonnegative Characteristic Form. American Math. Soc. u.a, 1973.