how to show this part only in the single post page?

I have this part in my index-meta.php file :

<ul>

                            <li class="Source"><a>source:</a></li>
                              <ul class="Source-Link">
                                <li><a href="<?php echo get_post_meta($post->ID, 'source-link', true); ?>" target="_blank"><?php echo get_post_meta($post->ID, 'source', true); ?></a></li>
                              </ul>

                        </ul>

this’ll show the source of my posts based on the custom fields I’ve made, and I just want them to show in the content-single.php file, I mean the single posts page. but they also showing in front page (index.php, content.php), I dont’ want that. what conditional can I use and how? please help me with this cause I’m pretty weak in php and wp…