https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-8-23
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-8-20
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-8-18
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-8-22
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-8-21
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-8-19