APA (7th ed.) Citation

Janeczek, Z., Warnke, P., & Warnke, U. (1982). Ex Libris Ursula + Pedro Warnke.

Chicago Style (17th ed.) Citation

Janeczek, Zbigniew, Pedro Warnke, and Ursula Warnke. Ex Libris Ursula + Pedro Warnke. 1982.

MLA (9th ed.) Citation

Janeczek, Zbigniew, et al. Ex Libris Ursula + Pedro Warnke. 1982.

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