http://www.military.com/military-fitness/fitness-test-prep/passing-military-swimming-tests

http://www.military.com/military-fitness/workouts/combat-swimmer-stroke

https://breakingmuscle.com/learn/swim-like-a-seal-how-to-do-the-combat-side-stroke

http://www.militaryforums.co.uk/forums/viewtopic.php?t=38587#.WKN1FTvyjIU

http://www.activeluton.co.uk/hydra-learn-to-swim

http://www.swimming.org/learntoswim/

http://www.wikihow.com/Swim

https://www.theguardian.com/lifeandstyle/the-swimming-blog/2013/nov/25/swimming-lessons-learning-via-internet-youtube

http://www.swimming.org/asa/clubs-and-members/swim-school-directory/

https://www.swimmersguide.com/