Hi David,
Welcome to the Group.
I've got Alain's book 'Calvados pour les Petits Trains', and love it. It took me a while to find one at a price I was willing to pay, from a French seller on eBay (?35 IIRC). I saw a copy once at an exhibition in Southampton but dawdled before buying and was beaten to it.
I can't comment on Henri's book.
I have joined a French Facebook group 'Le Calvados autrefois' which shows the area in old postcards, and CFC comes up from to time to time. There is also a French auction site delcampe.net which is searchable by location which might help re Caen.
Best wishes,
David H
David Hughes