How to reference "internal" libraries

I have an Aurelia project which is divided in several projects. My folder structure looks like this

/myApp 
  /.idea
  /myApp
  /myModule1
  /myModule2
  /myModule3

Each of those is a standalone jspm package (each have their own package.json file). Module myApp refers to myModule1, myModule1 and myModule3 via "jspm install".

in myApp/file.js I can do this:

import {Foo} from 'myModule1' //no file path here; this is referencing the logical name myModule1

but a WebStorm inspector warns me that myModule1 is not installed, therefore it can't give me autocomplete.

So my question is : How can I tell WebStorm about my internal libraries so that it recognizes their name and provide autocomplete?

Thanks