Author E. Herrett E. Williamson T. Van Staa M. Ranopa C. Free T. Chadborn B. Goldacre L. Smeeth Year of Publication 2016 DOI 10.1136/bmjopen-2015-010069 DOIGoogle ScholarBibTeXEndNote X3 XMLEndNote 7 XMLEndnote taggedMarcRIS
