As far as I know, Bob Proctor is the only person who has been studying personal development every day for more than half a century.
تا جایی که می‌دانیم، باب پراکتور (Bob Proctor) تنها کسی است که بیش از نیم قرن همه روزه درباره رشد شخصی مطالعه کرده است.