. 2015 Aug 13;4(3):e104. doi: 10.2196/resprot.4519
©Maarten van Limburg, Jobke Wentzel, Robbert Sanderman, Lisette van Gemert-Pijnen. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 13.08.2015.
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