An icon from icon theme <a href="//commons.wikimedia.org/wiki/Crystal_Clear" title="Crystal Clear">Crystal Clear</a> (svg version).
<ul><li><a href="//commons.wikimedia.org/wiki/File:Crystal_Clear_action_bookmark_Silver_doubt.svg" title="File:Crystal Clear action bookmark Silver doubt.svg">Crystal Clear action bookmark Silver doubt.svg</a>: *<a href="//commons.wikimedia.org/wiki/File:Crystal_Clear_action_bookmark_Silver.svg" title="File:Crystal Clear action bookmark Silver.svg">Crystal Clear action bookmark Silver.svg</a>: *<a href="//commons.wikimedia.org/wiki/File:Crystal_Clear_action_bookmark.svg" title="File:Crystal Clear action bookmark.svg">Crystal Clear action bookmark.svg</a>: <a href="https://en.wikipedia.org/wiki/Everaldo_Coelho" class="extiw" title="w:Everaldo Coelho">Everaldo Coelho</a> and <a rel="nofollow" class="external text" href="http://www.yellowicon.com">YellowIcon</a> (svg version by <a href="//commons.wikimedia.org/wiki/User:Actam" title="User:Actam">Actam</a>)</li></ul><p>derivative work: <a href="//commons.wikimedia.org/wiki/User:Henrykus" title="User:Henrykus">Henrykus</a> (<a href="//commons.wikimedia.org/wiki/User_talk:Henrykus" title="User talk:Henrykus">Henrykus</a>)
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<ul><li><a href="//commons.wikimedia.org/wiki/File:Vraagteken.svg" title="File:Vraagteken.svg">Vraagteken.svg</a>:</li>
<li>derivative work: <a href="//commons.wikimedia.org/wiki/User:Henrykus" title="User:Henrykus">Henrykus</a> (<a href="//commons.wikimedia.org/wiki/User_talk:Henrykus" title="User talk:Henrykus">Henrykus</a>)</li>
<li><a href="//commons.wikimedia.org/wiki/File:Crystal_Clear_action_bookmark.svg" title="File:Crystal Clear action bookmark.svg">Crystal Clear action bookmark.svg</a>: <a href="https://en.wikipedia.org/wiki/Everaldo_Coelho" class="extiw" title="w:Everaldo Coelho">Everaldo Coelho</a> and <a rel="nofollow" class="external text" href="http://www.yellowicon.com">YellowIcon</a> (svg version by <a href="//commons.wikimedia.org/wiki/User:Actam" title="User:Actam">Actam</a>)</li>
<li>derivative work: <a href="//commons.wikimedia.org/wiki/User:Henrykus" title="User:Henrykus">Henrykus</a> (<a href="//commons.wikimedia.org/wiki/User_talk:Henrykus" title="User talk:Henrykus">Henrykus</a>)</li></ul>
<p>Own work based on: <a href="//commons.wikimedia.org/wiki/File:Crystal_Clear_action_bookmark_Silver_doubt.svg" title="File:Crystal Clear action bookmark Silver doubt.svg">Crystal Clear action bookmark Silver doubt.svg</a>
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<ul><li><a href="//commons.wikimedia.org/wiki/File:Crystal_Clear_action_bookmark.svg" title="File:Crystal Clear action bookmark.svg">Crystal Clear action bookmark.svg</a></li></ul>