Tapio Seppänen Kaisu Mäkelä Anja Keskinarkaus Hiding Information in Color Images Using Small Color Palettes. 69-81 http://link.springer.de/link/service/series/0558/bibs/1975/19750069.htm 2000 conf/isw/2000 ISW db/conf/isw/isw2000.html#SeppanenMK00