Arjen K. Lenstra Eran Tromer Adi Shamir Wil Kortsmit Bruce Dodson James Hughes Paul C. Leyland Factoring Estimates for a 1024-Bit RSA Modulus. 55-74 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2894&spage=55 2003 conf/asiacrypt/2003 ASIACRYPT db/conf/asiacrypt/asiacrypt2003.html#LenstraTSKDHL03