1) All of Robin Sharma's books - especially The Monk who sold his Ferrari 2) The Conquest of Happiness by Bertrand Russell 3) Self Reliance by Ralph Waldo Emerson 4) The Meditations of Marcus Aurelius 5) Barking up the wrong tree by Eric Barker 6) This might be strange - but Harry Potter series also teach us a lot, especially about Courage and Conviction.
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