Impact of stringent non-pharmaceutical interventions applied during the second and third COVID-19 epidemic waves in Portugal, 9 November 2020 to 10 February 2021: an ecological study Torres, Ana Rita and Rodrigues, Ana Paula and Sousa-Uva, Mafalda and Kislaya, Irina and Silva, Susana and Antunes, Liliana and Dias, Carlos and Nunes, Baltazar, Eurosurveillance, 27, 2100497 (2022), https://doi.org/10.2807/1560-7917.ES.2022.27.23.2100497