Rómer Rosales Kannan Achan Brendan J. Frey Unsupervised Image Translation. 472-478 2003 conf/iccv/2003 ICCV http://csdl.computer.org/comp/proceedings/iccv/2003/1950/01/195010472abs.htm db/conf/iccv/iccv2003-1.html#RosalesAF03