Two metres or one: what is the evidence for physical distancing in covid-19?

Jones, N. R., Qureshi, Z. U., Temple, R. J., Larwood, J. P. J., Greenhalgh, T., & Bourouiba, L. (2020). Two metres or one: what is the evidence for physical distancing in covid-19? BMJ (Clinical Research Ed.), 370, m3223. https://doi.org/10.1136/bmj.m3223