Cita APA (7a ed.)

Youngken, H. W. (1921). A text book of pharmacognosy. P. Blakiston's son & co.

Cita Chicago Style (17a ed.)

Youngken, Heber Wilkinson. A Text Book of Pharmacognosy. Philadelphia: P. Blakiston's son & co, 1921.

Cita MLA (8a ed.)

Youngken, Heber Wilkinson. A Text Book of Pharmacognosy. P. Blakiston's son & co, 1921.