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. 2014 Jul 23;3(3):e31. doi: 10.2196/resprot.2599

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©Lenneke van Genugten, Pepijn van Empelen, Anke Oenema. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 23.07.2014.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work, first published in JMIR Research Protocols, is properly cited. The complete bibliographic information, a link to the original publication on http://www.researchprotocols.org, as well as this copyright and license information must be included.

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resprot_v3i2e31_app2.pdf^{(63.5KB, pdf)}