Elbadawy A. Kamoun, Andreas Winkel, Michael Eisenburger, Henning Menzel: Carboxylated camphorquinone as visible-light photoinitiator for biomedical application: Synthesis, characterization, and application. In: Arabian Journal of Chemistry. Elsevier, 2014, doi:10.1016/j.arabjc.2014.03.008.