The question I have for you is this?, is the book you have talked about. Did they come the UK and not the USA?. If they are from the UK did you read them or see them your self and was the book have Ben printed in the UK or the USA?. If they where printed in the USA they did not put every thing in the book as the people in the UK do.
Books I would like to add to James Starbird list. Kahn, D., (1991), Seizing the Enigma, Houghton Mifflin Co. Boston Sebag-Montefiore, H., (2000), Enigma: the Batle for the Code, London, Weidenfels & Nicolson. Barczak, C., (2014), A Indecifravel Enigma, Clube de Autores, São Paulo