Campbell, H., Li, Y., Kulkarni, D., Harpur, A., Nundy, M., Wang, X. & Nair, H. 2020, 'The temporal association of introducing and lifting non-pharmaceutical interventions with the time-varying reproduction number (R) of SARS-CoV-2:a modelling study across 131 countries', The Lancet Infectious Diseases, 21(2), pp. 193-202. https://doi.org/10.1016/S1473-3099(20)30785-4