Unusual Medoc Pocket Book book?

[Big Geoff]

I have started to thin down my collection of Fortification books and have come across two copies of this book.
It is soft cover and is titled HISTORIE D'UNE POCHE DE L'ATLANTIQUE , Les forces allemandes dand le Medoc.
The book cover the Pocket of South Gironde in astonishing detail, the forces, fortifications, organisation charts even down to the fortress telephone network. 200 pages in all including a few poor quality photographs.
I wondered what price to put on them on EBay, has anyone come across these publications before, if you can shed any light please PM me?
I did try to add a few photos but the technology has defeated me, again.