1. R. Guglielmetti, in: H. Dürr, H. Bouas-Laurent (Eds.), Photochromism: Molecules and Systems, Elsevier, Amsterdam, 1990, p. 314 (Chapter 8).
2. J.C. Crano, R.J. Guglielmetti (Eds.), Organic Photochromic and Thermochromic Compounds, Vols. 1/2, Plenum Press, New York, 1998–1999.
3. B. Van Gemert, in: J.C. Crano, R.J. Guglielmetti (Eds.), Organic Photochromic and Thermochromic Compounds, Vol. 1, Plenum Press, New York, 1998, p. 111 (Chapter 3).
4. Proof of structure of the colored photoproducts of chromenes and spiropyrans
5. F. Ortica, D. Levi, P. Brun, R. Guglielmetti, U. Mazzucato, G. Favaro, J. Photochem. Photobiol. A (2000).