McDonald R, Mead N, Cheraghi-Sohi S, Bower P, Whalley D. Governing the ethical consumer: identity, choice and the primary care medical encounter. Sociol Health Illn. 2007 Apr 1;29(3):430-56.
Campo R, Brullet E, Montserrat A, Calvet X, Rivero E, Brotons C. Topical pharyngeal anesthesia improves tolerance of upper gastrointestinal endoscopy: a randomized double-blind study. Endoscopy. 1995 Nov;27(9):659-64.