Garcia-Albeniz X, Chan AT. Aspirin for the prevention of colorectal cancer. Best Pract Res Clin Gastroenterol. 2011 Aug;25(0):461-72. doi: 10.1016/j.bpg.2011.10.015
McKenna SP, Whalley D, Doward LC. Which outcomes are important in schizophrenia? Int J Methods Psychiatr Res. 2000;9(1):S58-67.
López MV, Rivero E, Serra C, Campo M, Raurich M, Bonfill X. Health survey in health care professionals in Barcelona. Arch Prev Riesgos Laborales. 1998;1(2):55-62.