Adult coloring books are selling like crazy. Here's why. - Vox
My First 365 Coloring Book: Jumbo Coloring Book For Kids (With Tear Out Sheets): Wonder House Books: 9789390183005: Amazon.com: Books
My First Big Book Of Coloring - By Little Bee Books (paperback) : Target
Adorable Town Coloring Book: Explore the Kawaii World and the Little Creatures, A Cute Coloring Book for Adult: Dao, Lainie: 9798356537424: Amazon.com: Books