Mark L. Bauer Safuat Hamdy On Class Group Computations Using the Number Field Sieve. 311-325 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2894&spage=311 2003 conf/asiacrypt/2003 ASIACRYPT db/conf/asiacrypt/asiacrypt2003.html#BauerH03