A simple plus (+) sign for the ambox template. 
Derivative of <a href="//commons.wikimedia.org/wiki/File:Arrow_icon.svg" title="File:Arrow icon.svg">File:Arrow icon.svg</a>.
<a href="//commons.wikimedia.org/wiki/User:HuBoro" title="User:HuBoro">HuBoro</a>
<span class="int-own-work" lang="en">Own work</span>