Wallace Chigona Henry Sonnet Felix Ritter Thomas Strothotte Shadows with a Message. 91-101 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=2733&spage=91 2003 conf/sg/2003 Smart Graphics db/conf/sg/sg2003.html#ChigonaSRS03