https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-34
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-32
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-36
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-31
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-33
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-35
https://ij-healthgeographics.biomedcentral.com/articles/10.1186/1476-072X-11-37