Subtractive 4 color: pigment process, still photography
“Berger then started to work with the master carbro printer Richard Newmark Kauffman (1916−1998), and together they founded Ultrastable Color Systems, Inc. In 1992 they introduced presensitized UltraStable material for four-color carbon ...
Pénichon, Sylvie (2013): Twentieth Century Colour Photographs. The Complete Guide to Processes, Identification & Preservation. London, Los Angeles: Thames & Hudson, p. 95.