Sol-Gel Science: The Physics and Chemistry of Sol-Gel Processing by C. Jeffrey Brinker, George W. Scherer
Sol-Gel Materials: Chemistry and Applications by John D. Wright, Nico A.J.M. Sommerdijk
Sol-Gel Technologies for Glass Producers and Users by Michel A. Aegerter and M. Mennig
German Patent 736411 (applied for on 28 May 1939 and granted on 6 May 1943) Verfahren zur Änderung des Reflexionsvermögens optischer Gläser - Process for changing the reflection capacity of optical glass, Drs Walter Geffcken and Edwin Berger of the Jenaer Glasswerk Schott