TY  - JOUR
A1  - Zipf, G.K.
T1  - The P1P2/D hypothesis: On the intercity movement of persons
Y1  - 1946
DO  - 10.2307/2087063
UR  - https://doi.org/doi:10.2307/2087063
VL  - 11
IS  - 6

ER  -