Kass, D., Kauffman, J., & Herrera Reyes, C. (1995). Costa Rica: Reference soils of the Turrialba valley and slopes of the Irazú volcano. Soil brief Costa Rica 2.
استشهاد بنمط شيكاغوKass, D.C.L., J.H Kauffman, و C.G Herrera Reyes. Costa Rica: Reference Soils of the Turrialba Valley and Slopes of the Irazú Volcano. Soil Brief Costa Rica 2. 1995.
MLA استشهادKass, D.C.L., J.H Kauffman, و C.G Herrera Reyes. Costa Rica: Reference Soils of the Turrialba Valley and Slopes of the Irazú Volcano. Soil Brief Costa Rica 2. 1995.
تحذير: قد لا تكون هذه الاستشهادات دائما دقيقة بنسبة 100%.