Claus, Edward P. Pharmacognosy / Edward P. Claus, Varro E. Tyler and Lynn R. Brady. - 9th ed. - Philadelphia : Lea & Febiger, 1999. - xii, 518 p. : illus. (part col.) ; 24 cm. Includes index. Subjects--Topical Terms: Pharmacognosy. Dewey Class. No.: 615.321 / CLP