This paper reconsiders the production-location problem (PLP) initiated by M
oses. The PLP is extended to allow for the geographical substitution betwee
n input sources, which is likely to occur in an integrated market. An algor
ithm is then proposed to solve this problem. Finally, using numerical examp
les, it is shown that small variations in the elasticity of substitution of
the production function may lead to substantial jumps in the optimal firm
location.