https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-9-47
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-9-48
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-9-45
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-9-44
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-9-46