Forsythe, W., & Tafur, N. (2022). The effect of various of methods of land preparation on soil resistence to penetration and yields of corn (Zea mays L.) cassava (Manihot esculenta Crantz) and sweet potato (Ipomoea batatas L.) in association. I. Effect of croping systems and land preparation on the soil. Instituto Interamericano de Cooperación para la Agricultura (IICA).

Forsythe, W., and N. Tafur. The Effect of Various of Methods of Land Preparation On Soil Resistence to Penetration and Yields of Corn (Zea Mays L.) Cassava (Manihot Esculenta Crantz) and Sweet Potato (Ipomoea Batatas L.) in Association. I. Effect of Croping Systems and Land Preparation On the Soil. Instituto Interamericano de Cooperación para la Agricultura (IICA), 2022.

Forsythe, W., and N. Tafur. The Effect of Various of Methods of Land Preparation On Soil Resistence to Penetration and Yields of Corn (Zea Mays L.) Cassava (Manihot Esculenta Crantz) and Sweet Potato (Ipomoea Batatas L.) in Association. I. Effect of Croping Systems and Land Preparation On the Soil. Instituto Interamericano de Cooperación para la Agricultura (IICA), 2022.