APA (7th ed.) Citation

Vopĕnka, P., & Hájek, P. (1972). The theory of semisets / Petr Vopĕnka and Petr Hájek. North-Holland Publishing.

Chicago Style (17th ed.) Citation

Vopĕnka, Petr, and Petr Hájek. The Theory of Semisets / Petr Vopĕnka and Petr Hájek. Amsterdam ; London: North-Holland Publishing, 1972.

MLA (9th ed.) Citation

Vopĕnka, Petr, and Petr Hájek. The Theory of Semisets / Petr Vopĕnka and Petr Hájek. North-Holland Publishing, 1972.

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