Swartz, E. E., Belmore, K., Decoster, L. C., & Armstrong, C. W. (2010). Emergency face-mask removal effectiveness: A comparison of traditional and nontraditional football helmet face-mask attachment systems. Journal of athletic training, 45(6), S. 560-569. http://www.nata.org/sites/default/files/attr-45-06-pg-560-569.pdf

Swartz, Erik E., Keith Belmore, Laura C. Decoster, and Charles W. Armstrong. "Emergency Face-mask Removal Effectiveness: A Comparison of Traditional and Nontraditional Football Helmet Face-mask Attachment Systems." Journal of Athletic Training 45, no. 6 (2010): S. 560-569.

Swartz, Erik E., Keith Belmore, Laura C. Decoster, and Charles W. Armstrong. "Emergency Face-mask Removal Effectiveness: A Comparison of Traditional and Nontraditional Football Helmet Face-mask Attachment Systems." Journal of Athletic Training 45.6 (2010): S. 560-569.