1. Principles of gradient elution
2. “Gradient Elution Chromatography”;Liteanu,1974
3. H. Elgass, “Untersuchung zur Gradient Elution.” PhD Dissertation, Universität des Saarlandes, Saarbrücken, 1978.
4. “An Introduction to Modern Liquid Chromatography,” 2nd Ed., Chap. 16.;Snyder,1979
5. Gradient elution in liquid chromatography