Turner, Henry Ashby, Jr. Geissel des Jahrhunderts: Hitler und seine Hinterlassenschaft
What if: Hitler was killed in an auto accident in 1930.
Comments: Counterfactual analysis of what would then have (not) happened, including no Third Reich and World War II, but Germany as ruled by a military junta remains a great European power. Note that this theme is developed much more briefly in Turner's Hitler's Thirty Days to Power: January 1933.
Published: Siedler 1989 (3886803538).
Original in: German.