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. 2015 Dec 10;5:17890. doi: 10.1038/srep17890

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Map created using ESRI ArcGIS, ArcMap 10.1. Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/Airbus DS, USDA, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and the GIS User Community. For more information on this map, including the terms of use, visit: http://goto.arcgisonline.com/maps/World_Imagery.