The Black Nineteen is one of V.M. Straka's other works.
It is thought that The Black Nineteen may have been a confession of sorts for all of the crimes that V.M. Straka may or may not have committed.
The structure of The Black Nineteen is mimicked by Interlude in Ship of Theseus (book).
On page 262 of Karst's English edition of The Black Nineteen includes a identical description of Princip, a real life assassin of the archduke (of which V.M. Straka was allegedly involved).1)