APA (7th ed.) Citation

Gumkowski, J., & Leszczyński, K. 1. V. (1961). Poland under Nazi occupation. Polonia Publ. House.

Chicago Style (17th ed.) Citation

Gumkowski, Janusz, and Kazimierz 19XX-2010 VerfasserIn Leszczyński. Poland Under Nazi Occupation. Warsaw: Polonia Publ. House, 1961.

MLA (8th ed.) Citation

Gumkowski, Janusz, and Kazimierz 19XX-2010 VerfasserIn Leszczyński. Poland Under Nazi Occupation. Polonia Publ. House, 1961.

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