"In Search of the Wild Dulcimer" is by Robert Force and Albert d'Ossche. Artist Carole Palmer. Published by Amsco Music Publishing Company, New York. My edition is dated 1975.
It is a beautifully presented book and very easy to understand. It is a good companion book to Jean Richie's, I think. It is this book that gives the "Volkswagon" method, among many others, of holding a Dulcimer. If you can find a copy it's worth having. Joy