https://books.google.de/books?isbn=0470698225
Per A. F. H. Renström - 2008 - 336 pages - Medical
Table 1.1 Error margins for a groundstroke hit with different levels of spin and
speed. (Modified from Brody 1987.) Table 1.2 Error margins for a service hit at ...
https://books.google.de/books?isbn=1450424538
Table 15.6 Cause of Error Poor movement or Poor rituals, focus, or Poor stroke ...
I I LH-i'JJ-H' From The Tennis Parent's Bible (www.thetennisparentsbible.com).