Gamon, D. Building mental muscle: Conditioning exercises for the six intelligence zones. Viva Books.
Chicago-viite (17. p.)Gamon, David; Bragdon. Building Mental Muscle: Conditioning Exercises for the Six Intelligence Zones. Viva Books.
MLA-viite (9. p.)Gamon, David; Bragdon. Building Mental Muscle: Conditioning Exercises for the Six Intelligence Zones. Viva Books.
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