ng-dropzone module does not work in my AngularJS app

I am using ng-dropzone in my AngularJS and following the steps according to its documentation but I get the following error:

TypeError: o is not a constructor
at Object.link (http://localhost/myAngularJSApp/lib/bower/ng-dropzone/dist/ng-dropzone.min.js:1:440)

The sequence of loading dependencies are:

  1. angular.js
  2. dropzone.js
  3. ng-dropzone.min.js

I found out that all the files are loaded properly but I don’t know where is the problem!?

Source: AngularJS