I have the Gouby book, he gave it to me personally. I don't think he sells all that many, and even that is in need of an update. Putting a book on halfpennies in print would not be viable, but an electronic version, downloadable PDF or some kind of pay and view on the internet system would probably work. I could then mention it under the halfpenny section of CCGB2005...."For in depth specialist information on halfpennies, see www.rotographic.co.uk". Even at £2.00 a copy, when your selling something that involves no paper, no postage and no wrapping up, it could work. Anyway, I digress. Perhaps you could PM me Rob.