Event.observe(window, 'load', function(){

$$('ul.main_menu')[0].insert('<iframe src="//www.facebook.com/plugins/likebox.php?href=http%3A%2F%2Fwww.facebook.com%2Fpages%2FBritts-Klinik%2F164354726941747&amp;width=205&amp;height=290&amp;colorscheme=light&amp;show_faces=true&amp;border_color=%23000000&amp;stream=false&amp;header=true" scrolling="no" frameborder="0" style="border-right: 1px solid black; overflow:hidden; width:200px; height:290px;" allowTransparency="true" class="fb"></iframe>');
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