Here are a few early articles on the pony book, including Clarissa Cridland’s trailblazing article on the genre, and an article by author Susanna Forrest on the future of the pony book.
Pony Books – the Rules (Jane Badger)
Writing Pony Books – the Rules (Jane Badger)
Pony Books – an Introduction (Clarissa Cridland)
Why Girls Still Sign Up for the Pony Club ( Susanna Forrest)