Nancy Drew Original 13: The Mystery of the Ivory Charm

Blurb

The Mystery of the Ivory Charm is the thirteenth volume in the Nancy Drew Mystery Stories series. It was first published in 1936 under the pseudonym Carolyn Keene. The actual author was ghostwriter Mildred Wirt Benson.
This is one of the few Nancy Drew books where an acknowledgement has been made to Mildred Wirt Benson. The acknowledgement from the 1974 edition reads as follows:
"Acknowledgement is made to Mildred Wirt Benson, who under the pen name Carolyn Keene, wrote the original NANCY DREW books."