@article{Duncan2011,
author = {Duncan, D.T. and Aldstadt, J. and Whalen, J. and Melly, S.J. and Gortmaker, S.L.},
title= {Validation of Walk Score® for Estimating Neighborhood Walkability: An Analysis of Four US Metropolitan Areas},
year = {2011},
doi = {10.3390/ijerph8114160},
journal = {International Journal of Environmental Research and Public Health},
volume = {8},
number = {11},
pages = {4160--4179},
}