https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-5-47
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-5-51
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-5-49
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-5-50
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-5-48
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-5-52