@article{Matthews2009,
author = {Matthews, S.A. and Moudon, A.V. and Daniel, M.},
title= {Using geographic information systems (GIS) for enhancing research relevant to policy on diet, physical activity, and weight},
year = {2009},
doi = {10.1016/j.amepre.2009.01.011},
journal = {American Journal of Preventive Medicine},
volume = {36},
number = {4S},
pages = {171--176},
}