Here is a bit of Keatonablia I've never seen before. A c.1930 child's activity book called The Rapid Draughtsman. Made in Germany, the little book is the equivalent of today's "invisible coloring books." This antiquated version simply used a pencil (the edge of a coin might work too) to reveal an image on a blank page. Look what this page revealed.
Copies of this book are for sale. Here is the link with all the details, although there is no guarantee there will be another "Buster" contained within.