Ritter A, Mellor R, Chalmers J, Sunderland M, Lancaster K. Key considerations in planning for substance use treatment: estimating treatment need and demand. J Stud Alcohol Suppl. 2019 Jan;Supp1 18:22-30. doi: 10.15288/jsads.2019.s18.22
Fondell E, Lagerros YT, Sundberg CJ, Lekander M, Balter O, Rothman KJ, Balter K. Physical activity, stress, and self-reported upper respiratory tract infection. Med Sci Sports Exerc. 2011 Feb 1;43(2):272-9.