Drawing Cats: Guide to Colors by `Cedarseed on deviantART
An absolutely awe-inspiring (and very interesting) colour chart for domestic cats. It’s incredibly detailed, and also covers coat patterns, ticking, eye colour and pad colour. Somali/abyssinian colours are at the bottom, though the ‘silver’ variants of the main colours aren’t covered. I could look at this for hours, and am quite tempted to buy a print of it for my office wall.