APA (7th ed.) Citation

Gorzkowski Waldemar. (1990). XX International Physics Olympiad. World Scientific.

Chicago Style (17th ed.) Citation

Gorzkowski Waldemar. XX International Physics Olympiad. World Scientific, 1990.

MLA (8th ed.) Citation

Gorzkowski Waldemar. XX International Physics Olympiad. World Scientific, 1990.

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