1. J.F. Asmus, C.G. Murphy, W.H. Munk, in Developments in Laser Technology II, vol. 41, ed. by R.F. Wuerker. Proceedings of SPIE (1973), pp. 19–30
2. G. Orial. in Preservation and Restoration of Cultural Heritage: Proceedings of the 1995 LCP Congress, Montreux (Switzerland), 24–29 sept 1995; (1996), pp. 469–479
3. A. Giusti, C. Biliotti, C. Samarelli, OPD Restauro 8, 120–122 (1996)
4. G. Calcagno, M. Koller, J. Nimmrichter, in Laser Based, Cleaning on Stonework. Restauratoren Blätter. Special Issue: LACONA I (Vienna : St. Stephens Cathedral, 1997), pp. 39–43
5. C. Weeks, Studies in Conservation, vol. 43, pp. 101–108 (1998)