@article{O’Kelly2004,
author = {O’Kelly, M.E.},
title= {Isard’s contributions to spatial interaction modelling},
year = {2004},
doi = {10.1007/s10109-004-0125-4},
URL = {https://doi.org/doi:10.1007/s10109-004-0125-4},
volume = {6},
number = {1},
pages = {43‒54},
}