Comparison of the optical properties and UV radiation resistance of HfO2 single layers deposited by reactive evaporation, IAD, and PIAD, Thielsch, Roland, Feigl Torsten, Kaiser Norbert, Martin Sven, Scaglione Salvatore, Sarto Francesca, Alvisi Marco, and Rizzo Antonella , Proceedings of SPIE - The International Society for Optical Engineering, Volume 3902, Boulder, CO, USA, p.182-193, (2000)