Pavol Novotný Leonid I. Dimitrov Milos Srámek 370-373 2004 conf/cgi/2004 Computer Graphics International https://doi.org/10.1109/CGI.2004.1309235 https://doi.ieeecomputersociety.org/10.1109/CGI.2004.1309235 db/conf/cgi/cgi2004.html#NovotnyDS04