webpack error， Module not found: Error: Cannot resolve module ‘react’ in xxx

hi，I used webpack to build the react project when I encountered an error：

I have already installed react，Don’t know why webpack can’t find it….

this is webpack configure：

this is my package.json file:

webpack version is 1.12.14

react version is 0.14.7

Why doesn’t he work? Obviously have react, why can not find?

Who can help me? be deeply grateful!!