1. Bayer, O.; Siefken, W.; Rinke, H.; Orthner, L.; Schild, H. DRP 728981, 1937, (I. G. Farben).
2. Polyurethane Handbook,1994
3. Polyurethanes: Chemistry and Technology, Part I. Chemistry;Saunders,1962
4. Polyurethanes, Ullmann’s Encyclopedia of Industrial Chemistry;Adam,2005
5. Szycher’s Handbook of Polyurethanes;Szycher,1999