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Stanislav Grof
Stanislav Grof is a Czech-born American psychiatrist. Grof is one of the principal developers of transpersonal psychology and research into the use of non-ordinary states of consciousness for purposes of psychological healing, deep self-exploration, and obtaining growth and insights into the human psyche.
Excerpt from Wikipedia, available under CC BY-SA 4.0.
Books

The Holotropic Mind
2009
ISBN 9780061746871