Influence of heat treatment and γ-irradiation on the optical properties of methylene blue trihydrate thin filmsA. F. El-Deeb, M. M. El-Nahass, M. A. Kamel and S. Y. HuthailyEur. Phys. J. Appl. Phys., 41 1 (2008) 33-40DOI: https://doi.org/10.1051/epjap:2008001