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Sinclair, Christina D.; Stellino, Megan Babkes; Partridge, Julie A. (2008). "Recess Activities of the Week (RAW): Promoting Free Time Physical Activity to Combat Childhood Obesity". Strategies: A Journal for Physical and Sport Educators. 21 (5): 21–24. doi:10.1080/08924562.2008.10590788. S2CID73028181.
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(ASH), President’s Council on Sports, Fitness & Nutrition, Assistant Secretary for Health (July 20, 2012). "Physical Activity Guidelines for Americans". HHS.gov. Retrieved October 14, 2018.{{cite news}}: CS1 maint: multiple names: authors list (link)
Sinclair, Christina D.; Stellino, Megan Babkes; Partridge, Julie A. (2008). "Recess Activities of the Week (RAW): Promoting Free Time Physical Activity to Combat Childhood Obesity". Strategies: A Journal for Physical and Sport Educators. 21 (5): 21–24. doi:10.1080/08924562.2008.10590788. S2CID73028181.
Jarrett, Olga S.; Maxwell, Darlene M.; Dickerson, Carrie; Hoge, Pamela; Davies, Gwen; Yetley, Amy (1998). "Impact of Recess on Classroom Behavior: Group Effects and Individual Differences". The Journal of Educational Research. 92 (2): 121–126. doi:10.1080/00220679809597584. ISSN0022-0671.