@book{8123,
	author = {Bellman, Richard,},
	title = {Perturbation techniques in mathematics, engineering & physics /},
	publisher = {Dover Publications,},
	year = {2003},
	address = {Mineola, NY :},
	note = {Originally published: New York : Holt, Rinehart and Winston, ©1964 in series: Athena series; selected topics in mathematics}
}