Bernd Altmann Matthias Fitzi Ueli M. Maurer Byzantine Agreement Secure against General Adversaries in the Dual Failure Model. 123-137 http://link.springer.de/link/service/series/0558/bibs/1693/16930123.htm 1999 conf/wdag/1999 DISC db/conf/wdag/disc99.html#AltmannFM99