@article {44579,
	title = {Effect of gas density on the hydrodynamics of bubble columns and three-phase fluidized beds},
	volume = {81},
	year = {2003},
	pages = {846-852},
	publisher = {Canadian Journal of Chemical Engineering},
	author = {Macchi, Arturo and Bi, Hsiaotao and Grace, John R. and McKnight, Craig A. and Hackman, Larry}
}
