1. MANGASARIAN, O. L., Nonlinear Programming, McGraw-Hill, New York, New York, 1969.
2. DAX, A., The Relationship between Theorems of the Alternative, Least Norm Problems, Steepest Descent Directions, and Degeneracy: A Review, Annals of Operations Research, Vol. 46, pp. 11–60, 1993.
3. NIRENBERG, L., Functional Analysis, Lectures Given in 1960–1961, Notes by Lesley Sibner, New York University, 1961.
4. LUENBERGER, D. G., Optimization by Vector Space Methods, Wiley, New York, New York, 1969.
5. FARKAS, J., Über die Theorie der Einfachen Ungleichungen, Journal für Reine und Angewandte Mathematik, Vol. 124, pp. 1–24, 1902.