Não informado. (1987). The Journal of Agricultural Economics Research. U.S. Department of Agriculture.
Citação do estilo Chicago (17ª ed.)Não informado. The Journal of Agricultural Economics Research. Washington: U.S. Department of Agriculture, 1987.
Citação MLA (8ª ed.)Não informado. The Journal of Agricultural Economics Research. U.S. Department of Agriculture, 1987.
אזהרה: ציטוטים אלה לעיתים לא מדויקים ב 100%.