@article {k8,
	title = {Comments on a semigroup formalism for the description of phase and population relaxation processes},
	journal = {The Journal of Chemical Physics},
	volume = {72},
	year = {1980},
	pages = {4591{\textendash}4599},
	publisher = {AIP Publishing},
	author = {Kosloff, Ronnie and Rice, Stuart A}
}
