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.
Grzywacz JG, Quandt SA, Early J, Tapia J, Graham CN, Arcury TA. Leaving Family for Work: ambivalence and Mental Health Among Mexican Migrant Farmworker Men. J Immigr Minor Health. 2006 Jan 1;8(1):85-97.