[1] E Shigley James, F McClure Shane, M Moses Thomas. Gems & Gemology, 55, 457(2019).

[2] C Palke Aaron, D Renfro Nathan, Saeseaw Sudarat et al. Gems & Gemology, 55, 536(2019).

[3] J C Ferguson, P E Fielding. Chemical Physics Letters, 10, 262(1971).

[4] E Fritsch, G R Rossman. Gems & Gemology, 24, 3(1988).

[5] T R Douthit, J L Emmett. Gems & Gemology, 29, 250(1993).

[6] W Lichtman Jeff, Conchello José-Angel. Nature Methods, 2, 910(2005).

[7] Zhou Chunhui, Sturman Nicholas, Tsai Tsung-Han et al. Gems & Gemology, 56, 258(2020).

[8] Zhou Chunhui, Tsai Tsung-Han. Gems & Gemology, 56, 136(2020).

[9] X Jiang, Y Wang, Z Zhang et al. The Journal of Gemmology, 37, 144(2020).

[10] E B Hughes, R W Hughes, W Manorotkul. Ruby and Sapphire: A Gemologist's Guide. Bangkok, 151(2017).

[11] Michael Gaft. Modern Luminescence Spectroscopy of Minerals and Materials. Springer Berlin Heidelberg, 14(2005).

[12] S Marfunin Arnold. Luminescence, 141(1979).