This is the companion book to `Les sites V1 en Flandres et en Artois' (ISBN 2-9515840-0-8, published in 2000) and goes into great detail, including diagrams and a list of V1 launch sites in the region. Northwest France was home to over 450 V1 launch sites. The ISBN for this book is 2-9515840-1-6 and it was published in 2006. The book also mentions a website: http://www.SitesV1du-nord-de-la-France.com. Both books are available from the museum at Crecy en Ponthieu, northwest of Abbeville, near the site of the medieval battle of Crecy. Recently we stayed at the village of Gueschart a few miles to the East of Crecy, where I noticed a collection of apparently wartime concrete buildings, sited in hedgerows. I visited them on an evening's walkabout and correctly guessed what their purpose was, which was confirmed by this book and by a model in the museum. Photos to follow when I get them onto a CD.