missing documentation

Question

<script type="text/javascript" src="js/jquery.min.js"></script>

<script type="text/javascript" src=" js/Calendar3.js"></script>

<link rel="stylesheet" href="css/add.css" type="text/css" media="screen" /> ;

<link rel="stylesheet" href="utilLib/bootstrap.min.css" type="text/css" media="screen" />

Introduced above Code

is not provided in any of the four file courses.