There's a great book about all (or most) aircraft flown by Lufthansa:
Lufthansa: An Airline and Its Aircraft byR. E. G. Davies, published in 1991by Airlife Publishing; ISBN: 051757022X. I'd think there would be something in there about the 3 BV-222 they operated...
Here's a link to some detail pics of the beast...
http://www.warbirdsresourcegroup.org/LRG/bv222.html