The book in question is this-
...I wouldn't care what language it's in!
Jean-Baptiste seems to have grown up with many of the same artistic influences as I did, namely Arthur Rackham, Brian Froud, Alan Lee and Rien Poortvliet, who I consider to be the glorious quadrumvirate of faerie art.
Anyway, the book is a 104 page masterpiece of Faerie Art, full of everything from simple sketches all the way up to fully painted pieces like the one above. JB is one of those few artists that can make even a simple sketch look incredible, and his paintings are simply spectacular.
His books are rather difficult to come by, even on eBay! I picked up Celtic Faeries on Amazon UK and I have another of his books on the way from the same place, but those two books were the last copies Amazon had of those particular titles. But Amazon France is probably worth a look. If you'd like to see more of his work, check out his website at www.jbmonge.com/, I highly recommend you do!