Christensen T, Riis AH, Hatch EE, Wise LA, Nielsen MG, Rothman KJ, Toft Sorensen H, Mikkelsen EM. Costs and efficiency of online and offline recruitment methods: a web-based cohort study. J Med Internet Res. 2017 Mar 1;19(3):e58. doi: 10.2196/jmir.6716
Lanza FL, Sontag SJ, Ciociola AA, Sykes DL, Heath AT, McSorley DJ. Ranitidine bismuth citrate plus clarithromycin: a dual therapy regimen for patients with duodenal ulcer. Helicobacter. 1998 Sep;3(3):212-21.
Graham DY, Breiter JR, Ciociola AA, Sykes DL, McSorley DJ. An alternative non-macrolide, non-imidazole treatment for curing helicobacter pylori and duodenal ulcers: ranitidine bismuth citrate plus amoxicillin. Helicobacter. 1998 Jun;3(2):125-31.