1. Manager D. How many kids play baseball in the world? [Available from: https://www.dugoutmanager.com/how-many-kids-are-playing-baseball-in-the-world/ .
2. Web HSB. Probability of playing college and professional baseball [Available from: http://www.hsbaseballweb.com/probability.htm .
3. Ozanian M. Forbes-MLB teams worth $36 billion as team values hit record $1.2 billion average [Available from: http://www.thesportsadvisorygroup.com/resource-library/business-of-sports/forbes-mlb-teams-worth-36-billion-as-team-values-hit-record-1-2-billion-average/ .
4. • Conte S, Camp CL, Dines JS. Injury trends in Major League Baseball over 18 seasons: 1998–2015. Am J Orthop (Belle Mead NJ). 2016;45(3):116–23. This study represents the most recent examining injury trends in major league baseball. They examined injury incidence and amount of lost participation time between 1998–2015 using an MLB injury database. They found the incidence of injury to increase steadily during this period. Shoulder and elbow injuries were the cause of the most lost participation time. During the study period, MUCL injury incidence increased significantly and a significant number of pitchers had MUCL reconstruction surgery.
5. Position statement for adolescent baseball pitchers 2013 [Available from: http://www.asmi.org/research.php?page=research§ion=positionStatement .