The following links will give you some more information related to flying boats, catapult ships, the aeronautical history of Brazil, Mario Stoppani and lots more. Since web pages tend to change over time I have only included the top level addresses. Please note that I am not responsible for the contents of these other sites.
Dive into the world of Dornier Wal – where history takes flight!
The foundation is dedicated to preserve the aeronautical history of the Rio Grande do Norte state from 1922 to the end of World War II.
This link is also an entry point to the Brazilian, U.S. American and European chapter of the foundation. It will lead you to the foundation's model and research group as well.
You might also want to have a look at the Italian web site about the Memorial Mario Stoppani. It is maintained by Riccardo Stoppani.
Seefunknetz is a site maintained by a fellow radio officer. It gives detailed information about specific ships and their radio stations. You will find descriptions about two of the catapult ships stationed in the South Atlantic. Follow the menu "Seefunk-Fotos" --> "Seefunk-Stationen" and then search for Schwabenland / DOFW and Westfalen / DODB. You will also find information on the liners Cap Arcona / DHDL , Cap Polonio / DDCT and Columbus / QLVG.