1 error :
Uncaught (in promise) TypeError: Cannot read property ‘_compileAndLink’ of undefined at Object.window.ons.TabbarElement.rewritables.link
2 error :
Uncaught (in promise) TypeError: Cannot read property ‘_link’ of undefined

Starting page is defined like this:
<!DOCTYPE html>
<html ng-app="app">
<head>
<meta http-equiv="Content-Security-Policy" content="default-src * gap://ready; style-src 'self' 'unsafe-inline'; script-src 'self' 'unsafe-inline' 'unsafe-eval'"><!-- default-src 'self' gap://ready -->
<meta name="format-detection" content="telephone=no">
<meta name="msapplication-tap-highlight" content="no">
<meta name="viewport" content="user-scalable=no, initial-scale=1, maximum-scale=1, minimum-scale=1, width=device-width">
<link rel="stylesheet" type="text/css" href="css/font_awesome/css/font-awesome.min.css">
<link rel="stylesheet" type="text/css" href="css/ionicons/css/ionicons.min.css">
<link rel="stylesheet" type="text/css" href="css/material-design-iconic-font/css/material-design-iconic-font.min.css">
<link rel="stylesheet" type="text/css" href="css/onsenui.css"/>
<link rel="stylesheet" href="css/onsen-css-components-dark-theme.css">
<link rel="stylesheet" href="css/app.css"/>
<title>Title</title>
</head>
<body>
<ons-page>
<!--<ons-toolbar>{{}}</ons-toolbar>-->
<ons-tabbar position="auto" animation="slide">
<ons-tab page="templates/live.html" icon="ion-university, material:md-graduation-cap" label="Page1" active></ons-tab>
<ons-tab page="templates/program.html" icon="ion-ios-calendar, material:md-calendar" label="Page2"></ons-tab>
<ons-tab page="templates/social.html" icon="ion-share, material:md-share" label="Page3"></ons-tab>
</ons-tabbar>
</ons-page>
<script type="text/javascript" src="js/onsenui.min.js"></script>
<script type="text/javascript" src="js/angular.min.js"></script>
<script type="text/javascript" src="js/angular-onsenui.min.js"></script>
<script type="text/javascript" src="cordova.js"></script>
<script src="js/app.js"></script>
<script src="js/appServices.js"></script>
</body>
</html>
each page (tab-item) is in a different html file.
Why Onsen throws these errors?
Thanks in advance