If there is a book based on the animated movie FernGully who author?

There are several books related to the animated movie FernGully. Here are a few of them along with their authors:

* "FernGully: The Last Rainforest" (1992) - written by Diana Young

* "FernGully: The Adventure Begins" (1992) - written by Tony Johnston and Holly Covillo

* "FernGully: The Magical Quest" (1994) - written by Tony Johnston and Holly Covillo

* "FernGully: The Mystery of the Mists" (1995) - written by Holly Covillo and Tony Johnston