@article {oh1999thermal,
	title = {Thermal effects on the excited state absorption and upconversion process of erbium ions in germanosilicate optical fiber},
	journal = {Journal of non-crystalline solids},
	volume = {259},
	number = {1},
	year = {1999},
	pages = {51{\textendash}56},
	publisher = {Elsevier},
	author = {Pettit, Erin and Simpson, Jay and Oh, Kyunghwan and Morse, TF}
}
