Ember external js and global

In my Ember app I am trying to add the money.js external lib. I successfully achieved that by installing it with bower and then adding app.import('bower_components/money.js/money.js'); to my ember-cli-build.js.

money.js defines a global variable fx which is available all over my app. However I receive many JSHint Errors while building the app like:

components/purchase-form.js: line 41, col 29, 'fx' is not defined.

Ember docs states:

Typically, the application object is the only global variable. All other classes in your app should be properties on the Ember.Application instance, which highlights its first role: a global namespace.

I just wonder what is the proper way to import this kind of lib along with its global