The director, in the commentary on the DVD, says that he was inspired by the book "Caravan Towards Buddha" by Andre Migot. This book was titled "CARAVANE VERS BOUDDHA" when it was published in 1954, but can now only be found under its alternate (English) title, "Tibetan Marches" (translated by Peter Fleming). See also "Au Tibet sur les traces du Bouddha (Collection Itinéraires)" by André Migot.