KNIGHT,BRUCE WINTON. Economic Principles in Practice. Pp. xvii,606. New York: Farrar & Rinehart,Inc.,1939. $3.25. O'HARA,FRANK,et al. Economics: Principles and Problems. Pp. x,672. New York: D. Van Nostrand Co.,Inc.,1939. $3.50

KNIGHT,BRUCE WINTON. Economic Principles in Practice. Pp. xvii,606. New York: Farrar & Rinehart,Inc.,1939. $3.25. O'HARA,FRANK,et al. Economics: Principles and Problems. Pp. x,672. New York: D. Van Nostrand Co.,Inc.,1939. $3.50