Hallo Franck
Sorry that I had to wake you up
I figured there was something like this going on. Well my own source is Italian and comes from the researches of the the former Italian Air Britain Group led by Giorgio Apostolo.
Not that I want to detract sources from the 1930's but I think that the booklet about the Italian Capronis are very accurate indeed and that you can rely on what I have written
Source: I monoplani Caproni degli anni trenta by Aerofan
Cheers
Stig