(2019). Self-Discipline: Develop Daily Habits to Program Your Mind, Build Mental Toughness, Self-Confidence and WillPower. Independently Published.
Chicago-viite (17. p.)Self-Discipline: Develop Daily Habits to Program Your Mind, Build Mental Toughness, Self-Confidence and WillPower. USA: Independently Published, 2019.
MLA-viite (9. p.)Self-Discipline: Develop Daily Habits to Program Your Mind, Build Mental Toughness, Self-Confidence and WillPower. Independently Published, 2019.
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