I only know of one book in the U.S. that discusses issues with gunsmithing the Little Martini's and that is Frank DeHaas' book, Mr. Single Shot's Gunsmithing Idea book. The book has some very good information in it and some very wrong information in it. You can buy a copy here GunBookSales.com

When I was going to Gunmsithing school I use to correspond with Mr. De Haas quite frequently. I think if he knew what we have learned about the little Cadet Martini since the advent of the internet he most certainly would have revised some of what he wrote.