“Cardiorespiratory clinical response in the 6 minute walk test with double mask in smoking and non-smoking male between 40 and 60 years old”, Bol méd postgrado, vol. 37, no. 2, pp. 9–14, Apr. 2022, Accessed: Jul. 24, 2026. Available: https://revistas2.uclave.org/index.php/bmp/article/view/3792