Using Conditional Statement To Control Header image

I am currently using the code below to control the header image if a certain page is navigated to, in this case “About the Author” which is page 2.

<div id="header">
<img src="<?php bloginfo('template_url');
if(is_page('2')) {
echo '/images/header-about.jpg'; }
else { echo '/images/header.jpg'; } ?>" width="899" height="283" />
</div>

How would I add multiple statements, ie,

if(is_page('3')) {
echo '/images/header-links.jpg'; }
else { echo '/images/header.jpg'; } ?>" width="899" height="283" />