Fumitaka Hoshino Masayuki Abe Tetsutaro Kobayashi Lenient/Strict Batch Verification in Several Groups. 81-94 2001 conf/isw/2001 ISC http://link.springer.de/link/service/series/0558/bibs/2200/22000081.htm db/conf/isw/isc2001.html#HoshinoAK01