problem with calendar.js

[sgs1]

Hello, I've included calendar.js in my file, and I attach here the code.

<script type="text/javascript" src="cordova.js"></script> <script type="text/javascript" src="SQLitePlugin.js"></script> <script type="text/javascript" src="js/Calendar.js"></script> <script type="text/javascript" src="js/sincronizza_con_calendario.js"></script>

The error that I see is this before the execution of the creation of an event is this:

Object is not a constructor (evaluating 'new Calendar()') cordova.js:322

What I'm wrong?