1, 3, 11, 14, 15, 17, 16 http://www.clevelandclinicmeded.com/medicalpubs/diseasemanagement/infectious-disease/upper-respiratory-tract-infection (provided 28/07/2016)
2 http://www.cdc.gov/features/rhinoviruses (provided 29/07/2016)
4, 16 General medical knowledge
5, 7 http://www.emedmd.com/content/respiratory-tract-viruses (provided 28/07/2016)
6, 12, 13http://www.nhs.uk/conditions/Respiratory-tract-infection/Pages/Introduction.aspx (provided 28/07/2016)
8 http://www.who.int/topics/influenza/en
9, 11 http://www.who.int/mediacentre/factsheets/fs211/en (provided 28/07/2016)
10http://www.cdc.gov/flu/protect/keyfacts.htm (provided 28/07/2016)