522 books • 20 series
The Dune Buggy Mystery (Bobbsey Twins (Grosset & Dunlap Hardcover), #3) (Carousel Books)
The Missing Pony Mystery (Simon and Schuster Step-By-Step Encyclopedia of Practical Ga, #4) (Her the Bobbsey Twins)
Secret in the Pirate's Cave (Bobbsey Twins (Wanderer Books Paperback), #2) (Bobbsey Twins (Grosset & Dunlap Hardcover), #2)
Blue Poodle Mystery (Bobbsey Twins (Grosset & Dunlap Hardcover), #1) (Bobbsey Twins (Wanderer Books Paperback), #1) (Carousel Books)