This image was acquired from
wikimedia. It was marked as Public Domain or CC0 and is free to use. To verify, go to the source and check the information there.
M hnh cc khu vc kinh ca Colin Clark. en Clark's Sector Model vi hnh cc khu vc kinh ca Colin Clark Own work based on File Clark's Sector Model Kwnd other versions cczero Clark's Sector model
Page 2023 Free-images.com. All images are Public Domain