Cita APA (7th ed.)

Frio, A., & Price, E. (1979). Changes in cropping systems: Cale, Tanauan, Batangas, 1973-1977. Agricultural Economics Department, International Rice Research Institute.

Cita Chicago (17th ed.)

Frio, A.L, i E.C Price. Changes in Cropping Systems: Cale, Tanauan, Batangas, 1973-1977. Los Baños, Laguna: Agricultural Economics Department, International Rice Research Institute, 1979.

Cita MLA (9th ed.)

Frio, A.L, i E.C Price. Changes in Cropping Systems: Cale, Tanauan, Batangas, 1973-1977. Agricultural Economics Department, International Rice Research Institute, 1979.