1. Food Agriculture and Organization (FAOSTAT)
https://www.fao.org/faostat/en/#data/QC
2. USDA/NASS Quick Stats Database;National Agricultural Statistics Service, U.N
3. Roots and Tubers for the 21st Century: Trends, Projections, and Policy;Scott,2000
4. Origin, Distribution and Economic Importance;Loebenstein,2009
5. Marketing Sweetpotatoes in the United States: A Serious Challenge for Small-to-Moderate Volume Growers;Estes,2009