Call Validation Script For Form In Pop Up?

"<scr'+'ipt type="text/javascript" src="js/val_feedback_Email.js</scr'+'ipt>"

How should I call the js validation script for a feedback form that was document.written in a pop up?

I have a page which contains a button. Onclick it produces a pop up window that contains a small feedback form produced by document.write. This much works.

NOW I need to call the js validate script but nothing seems to work

I tried this is the head of the page

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

I tried this is the head of the doumnet.write part

"<scr'+'ipt type="text/javascript" src="js/val_feedback_Email.js</scr'+'ipt>"

How do I call the js script to validate the form in the pop up? Where if anywhere should it go?

THis is the start of my script

<script type="text/javascript">
var newWindow;
function subWrite() {
newWindow = window.open("","","status,height=500,width=700")

[Code]....