https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00268-6
https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00267-7
https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00270-y
https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00266-8
https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00269-5
https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00271-x
https://resource-allocation.biomedcentral.com/articles/10.1186/s12962-021-00272-w