British Journal of General Practice· Tập 68 Số 670 ·Trang e301-e310·2018
Knut Holtedahl, Peter Hjertholm, Lars Borgqúist, Gé Donker, Frank Buntinx, David Weller, Tonje Braaten, Jörgen Månsson, Eva Lena Strandberg, Christine Campbell, Joke C. Korevaar, Ranjan Parajuli