HoleyCrap. There's more than one? Uh... well... I guess it looks like the one upthread. Though, as I study it, maybe that's not exactly the same one.
Now I'm all perfuddled.
According to the Wikipedia entry, he did a series of 16 "dog" pictures for a cigar company's advertising campaign. Nine of the 16 featured dogs playing poker... some of them may depict different events in the same game.
Google will get you all of them!