Popular Science, helmikuu 1944
A Color Index that aids in finding colors that match or harmonize has been brought out by the Container Corporation of America, of Chicago. Each of the index's six bakelite containers holds 14 celluloid cards, on each of which are eight removable plastic chips of harmonizing color. The index also includes two work charts on which the chips can be placed, either in a circle or in a diamond-shaped arrangement, for purposes of comparison. The full range of the index is 680 colors.