?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.aufirst=F&rft.au=Ball%2C+F&rft.aulast=Ball&rft.atitle=Seven+challenges+for+metapopulation+models+of+epidemics%2C+including+households+models&rft.volume=10&rft.date=March+2015&rft.pages=63-67&rft.issn=1755-4365&rft.title=Epidemics&rft.genre=article