1. http://www.patient.co.uk/doctor/chondrodermatitis‐nodularis(last accessed October 2014).
2. http://emedicine.medscape.com/article/994550‐treatment
3. http://www.patient.co.uk/doctor/otitis‐externa‐and‐painful‐discharging‐ears#ref‐11(All last accessed October 2014.)
4. http://emedicine.medscape.com/article/845525‐overview
5. There is a section on necrotizing OE inhttp://www.nhs.uk/Conditions/Otitis‐externa/Pages/Complications.aspx(All last accessed October 2014.)