@article {k42,
	title = {A direct relaxation method for calculating eigenfunctions and eigenvalues of the Schr{\"o}dinger equation on a grid},
	journal = {Chemical Physics Letters},
	volume = {127},
	year = {1986},
	pages = {223{\textendash}230},
	publisher = {Elsevier},
	author = {Kosloff, R. and Tal-Ezer, H}
}
