Supitcha Chotikhamjorn. (2021) Study of Production Efficiency and Maize Farmers' Incomes in Phetchabun Province. <i>Humanities and Social Sciences Journal of Pibulsongkram Rajabhat University</i>, <i>15</i>(2), 317-330.Supitcha Chotikhamjorn. "Study of Production Efficiency and Maize Farmers' Incomes in Phetchabun Province". Humanities and Social Sciences Journal of Pibulsongkram Rajabhat University 15 (2021):317-330.Supitcha Chotikhamjorn. Study of Production Efficiency and Maize Farmers' Incomes in Phetchabun Province. Pibulsongkram Rajabhat University:ม.ป.ท. 2021.