diff --git a/app/models/dotation.rb b/app/models/dotation.rb
index 416264b..3e02b4b 100644
--- a/app/models/dotation.rb
+++ b/app/models/dotation.rb
@@ -177,7 +177,12 @@ class Dotation < ApplicationRecord
     ret = full_descr
     doc = Nokogiri::HTML(ret)
     doc.css('iframe').each do |iframe|
-      url = 'https:' + iframe['src']
+      if iframe['src'].include? 'https'
+        url = iframe['src']
+      else
+        url = 'https:' + iframe['src']
+      end
+
       new_node = doc.create_element 'a'
       new_node['href'] = url
       new_node.inner_html = url