Sort Posts on Category Page Alphabetically

I am attempting to do as the topic describes: on category pages display all the posts in that category on one page alphabetically (by title).

I am using the following code to do this currently:

<?php
$postslist = get_posts('numberposts=100&order=ASC&orderby=post_title');
foreach ($postslist as $post) : start_wp(); ?>
<li><a href="<?php the_permalink() ?>"><?php the_title(); ?></a> |
			<small>
			Posted on <?php the_time('M d Y');?>
			</small>

			</li>
<?php endforeach; ?>

It works.. but the problem currently is that it creates empty lines for all the posts, including ones not in that category.

As that probably didn’t make much sense, see https://users.ice-berg.net/worldspinsmadlyon/?cat=3

What am I doing wrong currently?

Thanks in advance