Fischer A, Zimovetz E, Ling C, Esser D, Shoof N. Humanistic and cost burden of systemic sclerosis: a review of the literature. Autoimmun Rev. 2017 Nov;16(11):1147-54. doi: 10.1016/j.autrev.2017.09.010
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.