Cita APA

Campbell, R. K., & Sugano, A. I. (1989). Seed zones and breeding zones for White Pine in the Cascade Range of Washington and Oregon. Oregón: United States Department of Agriculture.

Citación estilo Chicago

Campbell, Robert K., and Albert I. Sugano. Seed Zones and Breeding Zones for White Pine in the Cascade Range of Washington and Oregon. Oregón: United States Department of Agriculture, 1989.

Cita MLA

Campbell, Robert K., and Albert I. Sugano. Seed Zones and Breeding Zones for White Pine in the Cascade Range of Washington and Oregon. Oregón: United States Department of Agriculture, 1989.