@book{66350,
	author = {Sulkin, Allan.},
	title = {PBX systems for IP telephony },
	publisher = {McGraw-Hill,},
	year = {2002.},
	address = {New York :},
	note = {Includes index.},
	url = {http://www.loc.gov/catdir/bios/mh041/2002512119.html}
}