Asthma Factsheet. Retrieved on 4 May 2020 from https://www.who.int/news-room/fact-sheets/detail/asthma (31 August 2017)
Living with Asthma. Retrieved on 4 May 2020 from http://www.aaa.org.sg/asthma/ (n.d.)
Asthma. Retrieved on 4 May 2020 from https://www.healthhub.sg/a-z/diseases-and-conditions/11/asthma. (14 June, 2019.)
Asthma May Raise Risk of COPD, Emphysema. Retrieved on 4 May 2020 from https://www.webmd.com/lung/copd/news/20040712/asthma-may-raise-risk-copd-emphysema#1 (12 July, 2004).
Patients with breathing, lung problems at highest risk with COVID-19: Study. Retrieved on 8 May 2020 from https://www.channelnewsasia.com/news/world/coronavirus-covid-19-study-lung-problems-at-risk-12554006. (19 March 2020)
People with Moderate to Severe Asthma. Retrieved on 4 May 2020 from https://www.cdc.gov/coronavirus/2019-ncov/need-extra-precautions/asthma.html (2 April, 2020).
Covid-19 and Asthma: What Patients Need to Know. Retrieved on 4 May 2020 from https://www.aaaai.org/conditions-and-treatments/library/asthma-library/covid-asthma. (23 April 2020).
Covid-19. Retrieved on 8 May 2020 from https://www.asthmafoundation.org.nz/your-health/covid-19. (27 April 2020)
Asthma Triggers: Flu (Influenza). Retrieved on 4 May 2020 from https://www.aafa.org/influenza-flu-triggers-asthma-complications/. (October 2015).
Qu YL, Liu J, Zhang LX, et al. "Asthma and the risk of lung cancer: a meta-analysis". Retrieved on 6 May 2020 from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5355290/. (n.d.).
What is the link between asthma and pneumonia? Retrieved on 6 May 2020 from https://www.medicalnewstoday.com/articles/325312#difference-between-asthma-and-pneumonia. (29 May, 2019)