Mössbauer study of the vibrational anisotropy and of the light-induced population of metastable states in single-crystalline guanidinium nitroprussideV. Rusanov, H. Winkler, C. Ober and A. X. TrautweinEur. Phys. J. B, 12 2 (1999) 191-198DOI: https://doi.org/10.1007/s100510050995