More than 70 years after his death, Adolf Hitler's notorious manifesto is set to go back on sale in German bookstores, NBC News reported.

Historians are readying a new, annotated edition of the Nazi leader's "Mein Kampf" which will be released in January. The Munich-based Institute of Contemporary History (IFZ) — a government-funded research institution — plans to publish it once the copyright to the text expires at the end of the year.

It will feature a total of 3,700 comments providing analysis on its content — which doubles the number of pages of the original version.

IFZ's Christian Hartmann told NBC News Hitler's "800-page book is in great parts anti-Semitic" and "full of allusions and assertions, which are difficult to understand in the 21st century," which is why every sentence will be explained and critically evaluated in the upcoming edition.

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