APA
U.S. Department of Agriculture, . (1967). Farm retail price spreads for dairy products, 1939-66. Washington, D.C: U.S. Department of Agriculture.
Chicago
U.S. Department of Agriculture, . 1967. Farm retail price spreads for dairy products, 1939-66. Washington, D.C: U.S. Department of Agriculture.
Harvard
U.S. Department of Agriculture, . (1967). Farm retail price spreads for dairy products, 1939-66. Washington, D.C: U.S. Department of Agriculture.
MLA
U.S. Department of Agriculture, . Farm retail price spreads for dairy products, 1939-66. Washington, D.C: U.S. Department of Agriculture. 1967.