Snoopy blue button

Illustration of Snoopy wearing a button with the same image on it, on a blue background

Snoopy is Charlie Brown's pet dog in the Peanuts comic strip by Charles M. Schulz. Snoopy was introduced in 1950 but was not anthropomorphized or drawn as walking on his hind legs until 1956. 

The Droste effect or the effect of a picture appearing within itself in a location where the said picture is likely to appear. Thus, Snoopy's likeness appears multiple times since he is wearing a button of himself wearing that button.