APA (7th ed.) Citation

Okhrimenko, C. A., & Targonskij, A. L. (2013). Extremal problems on ray systems.

Chicago Style (17th ed.) Citation

Okhrimenko, C. A., and A. L. Targonskij. Extremal Problems on Ray Systems. 2013.

MLA (8th ed.) Citation

Okhrimenko, C. A., and A. L. Targonskij. Extremal Problems on Ray Systems. 2013.

Warning: These citations may not always be 100% accurate.