@book{14892,
	author = {International Conference Singular Optics (Optical Vortices) and Soskin, Marat S., ed.},
	title = {Singular optics (optical vortices)},
	publisher = {The International Society for Optical Engineering},
	year = {2001},
	series = {SPIE proceedings series; v. 4403},
	address = {Washington, D. C.}
}