Non-Fiction: The Pyramid Principle - Logic in Writing and Thinking. Although the writing techniques the author presents sound obvious in hindsight, having them all-in one place as an comprehensive framework you can follow helped me a lot for the writing and research in my work Fiction: The Black Lizard Big Book of Locked-Room Mysteries A curated and annotated collection of locked-room mystery stories. All the stories are accompagnied by a small introduction into the author and the main character written by the curator. His enthousiasm shows in these small introductions, making the stories themselves even better.
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