Here is THE book to get him if you can find a copy...
FRENCH AIRCRAFT BEFORE THE GREAT WAR
Author Opdycke, L
Description 288pp,A4,840+ills,draws,Hb Catalogue of aircraft from the nearly 700 French builders who existed before the onset of WW1. It includes over 840 b/w photographs and line drawings.
Price: £49.95
I think it's out of print so you need to search the web.
This place has a copy..
http://solutions-express.co.uk/books/display.asp?productid=6639
But also try a search here..
www.bookfinder.com
He also NEEDS a subscription to WW1 Aero magazine published by Opdycke. It only comes out a few times a year but has great articles and line drawings. Subscriptions are tax deductible in the USA. More info..
http://www.aviation-history.com/ww1aero.htm
Colin
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