Transformational teaching and child psychological needs satisfaction, motivation, and engagement in elementary school physical education
Sport Exercise and Performance Psychology (2012) - Comment
doi: 10.1037/a0028635  issn: 2157-3913  issn: 2157-3905 

Alexandra H. Wilson, Yan Liu, Sharon E. Keith, Alexandra H. Wilson, Lindsey E. Kermer, Bruno D. Zumbo, Mark R. Beauchamp