APA ציטוט

Obourn, E. S., & Heiss, E. D. (1936). Modern science problems: A textbook in general science. Webster Pub. Co..

Chicago Style (17th ed.) Citation

Obourn, Ellsworth Scott, and Elwood D. Heiss. Modern Science Problems: A Textbook in General Science. St. Louis, Mo.: Webster Pub. Co., 1936.

ציטוט MLA

Obourn, Ellsworth Scott, and Elwood D. Heiss. Modern Science Problems: A Textbook in General Science. Webster Pub. Co., 1936.