'Utøya', named after the island where the far-right extremist carried out his gun massacre, describes the events in minute-by-minute detail.
Controversially, it is written in the first person, taking the point of view of the killer, with all of his thoughts, beliefs and feelings depicted with unnerving clarity.
Author Laurent Obertone studied police reports and court documents and spoke to witnesses and survivors to build up a detailed picture of the events, before imaginatively entering the mind of the mass murderer.
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"This is not about some kind of acceptance," David Serra, the book's publisher, told the newspaper. "Obertone is totally against Breivik's actions and is not looking for scandal."