The Simpsons: Yellow Bellied Yak, Loudmouth Leopard & Clutzy Cat

Look! This is Yellow Bellied Yak, Loudmouth Leopard, and Clutzy Cat in The Simpsons Episode called "HOMR". I wonder what TV Show were Yellow Bellied Yak, Loudmouth Leopard, and Clutzy Cat from. The Blocky and Oxwinkle Show that Stu and Dru watched it when they were Babies in Rugrats Episode called "Sour Pickles"? Lisa asked that the Voice of Yellow Bellied Yak was very similar to the cowardly Lion, Comic Book Guy told the Man that Loudmouth Leopard was a Ripoff of Jackie Gleason and Professor Frink told the Man that Clutzy Cat sounded exactly like Jerry Lewis. I'm sure Yellow Bellied Yak, Loudmouth Leopard and Clutzy Cat were other Characters in "The Blocky and Oxwinkle Show" besides Blocky the Block Figure and Oxwinkle the Ox.