Image not showing up in sidebar

I have decided to put logo in sidebar but I get a box with no image and question mark inside it. I also tried using a text widget, with no luck. Here is my current sidebar code;

<div class="sidebar">
<img src="url_of/https://www.musicianstelevision.com/wordpress/wp-content/uploads/2009/01/mtn_mulitco_logo.png"
width="140" height="200" />
<?php
/* if the current pages has a parent, i.e. we are on a subpage */
if ( $post->post_parent) {
	$parent_title = get_the_title($post->post_parent);
	$parent_link = get_permalink($post->post_parent);
	$children = wp_list_pages("title_li=&include=".$post->post_parent."&echo=0");
// list the parent page
	$children = wp_list_pages("depth=1&title_li=&child_of=".$post->post_parent."&echo=0");
// append the list of children pages to the same
}																							// $children variable

/* else if the current page does not have a parent, i.e. this is a top level page */
else {
	$parent_title = get_the_title($post->ID);
	$children = wp_list_pages("title_li=&include=".$post->ID."&echo=0");
	$children = wp_list_pages("depth=1&title_li=&child_of=".$post->ID."&echo=0"); // form a list of the children of the current page
}

if ($children) {
	echo "<div style='float: right; width: 220px; padding-top: 25px; height: 100%;'>";
        echo "<a href='" . $parent_link . "'>" . $parent_title . "</a>";
	echo "<ul style='list-style: none; padding-left: 20px;'>";
	echo $children; /*print list of pages*/
	echo "</ul>";
	echo "</div>";
} ?>
</div>
</div>