APA (7th ed.) Citation

Sierpiński, W., & Sierpinski, W. (1970). 250 problems in elementary number theory. American Elsevier [u.a.].

Chicago Style (17th ed.) Citation

Sierpiński, Wacław, and Waclaw Sierpinski. 250 Problems in Elementary Number Theory. New York: American Elsevier [u.a.], 1970.

MLA (9th ed.) Citation

Sierpiński, Wacław, and Waclaw Sierpinski. 250 Problems in Elementary Number Theory. American Elsevier [u.a.], 1970.