The Tibetan Book of the Dead. Robert Thurman

The Tibetan Book of the Dead was written by the great teacher Padmasambhava in the 8th or 9th century for Indian and Tibetan Buddhists. He hid the book until later times, and in the 14th century it was found by the famous book treasure hunter Karma Lingpa. The book describes the experience of the Gap (Tib. bardo), usually referring to the state between death and a new rebirth, according to the expectations of initiates into a special esoteric mandala (sacred universe) one hundred merciful and formidable Buddhist deities.
This book is an ancient treatise on the transition to another world, which teaches you to accept death as a given, freeing you from fear and helping to preserve your own dignity and presence of mind until the very end.