1. M. S. Tswett, Chromatographic adsorption analysis (selected works). USSR, Academy of Sciences, 1946. (In Russian).
2. G. Hesse, H. Weil, Michael Tswett's first paper on chromatography. M. Woelm, 1954.
3. Archiv of Botanical Garden of Geneva University.
4. H. Purnell, Gas Chromatography, John-Willy, 1968. p. 1.