APA
U.S. Department of Agriculture, . (1969). Quality indexes of U.S. agriculture exports and imports. Washington, D.C: Department of Agriculture.
Chicago
U.S. Department of Agriculture, . 1969. Quality indexes of U.S. agriculture exports and imports. Washington, D.C: Department of Agriculture.
Harvard
U.S. Department of Agriculture, . (1969). Quality indexes of U.S. agriculture exports and imports. Washington, D.C: Department of Agriculture.
MLA
U.S. Department of Agriculture, . Quality indexes of U.S. agriculture exports and imports. Washington, D.C: Department of Agriculture. 1969.