TY - JOUR A1 - O’Kelly, M.E. T1 - Isard’s contributions to spatial interaction modelling Y1 - 2004 DO - 10.1007/s10109-004-0125-4 UR - https://doi.org/doi:10.1007/s10109-004-0125-4 VL - 6 IS - 1 ER -