Olaf Müller Michael Nüsken Never Trust Victor: An Alternative Resettable Zero-Knowledge Proof System. 79-92 2002 conf/indocrypt/2002 INDOCRYPT http://link.springer.de/link/service/series/0558/bibs/2551/25510079.htm db/conf/indocrypt/indocrypt2002.html#MullerN02