G. E. Mathisen, R. M. Jensen, in S. A. Pettersen, „Aerobic Games and Playful exercises in 9-Year-Old Boys: Intensity and Fitness Effects“, REI, let. 9, št. 1/2, str. 57–64, apr. 2016, Pridobljeno: 8. november 2025. [Na spletu]. Dostopno na: https://old.journals.um.si/index.php/education/article/view/374