Zetou Ελένη, Koltsis Χρήστος, and Vernadakis Νικόλαος. 2013. “The Effect of Expert Model Observation on the Performance and Learning the Backstroke of Young Swimmers”. Inquiries in Physical Education and Sport 11 (2):58-67. https://doi.org/10.26253/heal.uth.ojs.ispe.2013.1401.