Predicting performance times from deliberate practice hours for triathletes and swimmers: what, when, and where is practice important?
Journal of Experimental Psychology Applied (2004) - Comment
pubmed: 15598120  doi: 10.1037/1076-898x.10.4.219  issn: 1939-2192  issn: 1076-898x 

Nicola J. Hodges, Tracey Kerr, Janet L. Starkes, Patricia L. Weir, Angela Nananidou