References

Retrieve from.https://www.google.com.ph/search?q=elastic+collision&oq=elastic+&aqs=chrome.1.69i57j0l5.5577j0j4&sourceid=chrome&ie=UTF-8
Retrieve from https://en.wikipedia.org/wiki/Elastic_collision
Retrieve from. https://www.youtube.com/watch?v=J9xOMPPJNm0
Retrieve from www.athleticscholarships.net/history-of-soccer-football.htm
Retrieve from https://en.wikipedia.org/wiki/Inelastic_collision
Retrieve from http://www.dummies.com/education/science/physics/how-to-determine-whether-a-collision-is-elastic-or-inelastic/
Retrieve from https://encrypted-tbn3.gstatic.com/images?q=tbn:ANd9GcRi2SmEzR2PIb6Rmcy4Q18bPL9hxB0I5tM04z77_Hl6GcJbP0eIHQ