A nice touch is the certificate of completion at the end of this activity book.
Die Grosse Flucht by Jurgen Thorwald German Hardcover 1979 512 Pages DJ
What stands out is the illustrated case cover under the dust jacket.
Philosophiae Naturalis Principia Mathematica 1687 By Newton [Leather Bound]
You will find that this activity book has a calming effect with its coloring pages.
