storage/templates/core/subscribe-buttons.twig
<div class="subscribe">
<h3>Subscribe</h3>
<a href="/rss.xml"
id="subscribe-button" class="btn btn-block btn-lg subscribe-button-rss btn-warning">Subscribe via
RSS</a>
<a href="https://itunes.apple.com/de/podcast/free-geek.fm-matthew-setter/id1018923368?l=en&mt=2"
id="subscribe-button" class="btn btn-block btn-lg subscribe-button-itunes btn-info">Subscribe on
iTunes!</a>
<a href="http://subscribeonandroid.com/freethegeek.fm/rss.xml"
id="subscribe-button" class="btn btn-block btn-lg subscribe-button-itunes btn-success">Subscribe on
Android!</a>
<a href="http://feeds.soundcloud.com/users/soundcloud:users:167269271/sounds.rss"
id="subscribe-button" class="btn btn-block btn-lg subscribe-button-rss btn-warning">Subscribe on
SoundCloud</a>
</div>