Bahá’í: World Faith for Modern Man
From Bahaipedia

Bahá'í: World Faith for Modern Man is a short introductory text about the Bahá'í Faith by Arthur L. Dahl.
It was published by the Bahá'í Publishing Trust in 1960. A revised edition was published in 1972 and reprinted in 1975.

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Bahá’í: World Faith for Modern Man