Steve Lawrence David M. Pennock Gary William Flake Robert Krovetz Frans Coetzee Eric J. Glover Finn Årup Nielsen Andries Kruger C. Lee Giles Persistence of Web References in Scientific Research. 26-31 2001 34 IEEE Computer 2 http://computer.org/computer/co2001/r2026abs.htm db/journals/computer/computer34.html#LawrencePFKCGNKG01