Cita APA (7th ed.)

Johnson, V. A., & Mattern, P. J. (1977). Genetic improvement of productivity and nutritional quality of wheat. Annual report. A.I.D. R & D Report Distribution Center.

Cita Chicago (17th ed.)

Johnson, V. A., i P. J. Mattern. Genetic Improvement of Productivity and Nutritional Quality of Wheat. Annual Report. Ann Arbor: A.I.D. R & D Report Distribution Center, 1977.

Cita MLA (9th ed.)

Johnson, V. A., i P. J. Mattern. Genetic Improvement of Productivity and Nutritional Quality of Wheat. Annual Report. A.I.D. R & D Report Distribution Center, 1977.