@article{douglis1998t,
	author={Douglis, F. and Ball, T. and Chen, Y.F. and Koutsofios, E.},
	journal={World Wide Web},
	number=1,
	pages={27--44},
	publisher={Springer},
	title={{The AT\&T Internet Difference Engine: Tracking and viewing changes on the web}},
	volume=1,
	year=1998,
}