WordPress shortcode loads a PDF file on your site in an iframe using Google Docs

load-pdf.php

<?php

/**
 * WordPress shortcode loads a PDF file on your site in an iframe using Google Docs.
 *
 * Example: [embed_pdf width="600px" height="500px"]http://infolab.stanford.edu/pub/papers/google.pdf[/embedpdf]
 */
function embed_pdf($attr, $url) {
    return '<iframe src="http://docs.google.com/viewer?url=' . $url . '&embedded=true" style="width:' .$attr['width']. '; height:' .$attr['height']. ';" frameborder="0">Your browser should support iFrame to view this PDF document</iframe>';
}
add_shortcode('embed_pdf', 'embed_pdf');