UGBE, Thomas adidaumbe; AKPAN, Stephen; OFEM, Ajah. Application of Kuhn-Tucker Optimality Criteria in the Selection of Fertilizer Combination for Crop Optimal Yield. American Scientific Research Journal for Engineering, Technology, and Sciences, Jordan, v. 14, n. 3, p. 279–288, 2015. Disponível em: https://asrjetsjournal.org/American_Scientific_Journal/article/view/1072. Acesso em: 3 nov. 2025.