Luftfahrt International Nr.11
This issue of Luftfahrt International has a 46 page article on the
technical construction of the BV 138. Many pictures, drawings and
technical facts but no operational history at all.
The magazine also has a 16 page article of the catapult ship Westfalen
and her pre-war career as support base for the Germany-South America
mail flights made by Lufthansa. Many illustrative pictures and drawings
too.
In german.