Historical basis for high-tier German BB's

[Ensign_Cthulhu]

As far as I am aware, none of the books I've ever read about projected German capital ships beyond the Bismarck and Tirpitz make any mention of ships bearing TRIPLE 16 inch guns - they all appear to have had eight twin mounts (and there were supposed to be some variants which were planned to have up to 4 twin TWENTY inch).

This being the case, can someone please point me to a reliable historical reference for the Tier IX German BB's? 

[Valdez_Raptor]

Plan Z has what you are looking for.  They were also sort of outlined in Hitler's second book.

[Goose21891]

Triple mounts are based on ones designed by Germany for Soviet Russia in the late 1930s, according to the Devs.