diff --git a/lib/issues_show_hook_listener.rb b/lib/issues_show_hook_listener.rb
index b3a23e1..3539588 100644
--- a/lib/issues_show_hook_listener.rb
+++ b/lib/issues_show_hook_listener.rb
@@ -32,6 +32,7 @@ class IssuesShowHookListener < Redmine::Hook::ViewListener
       issue.qbo_invoice_ids.each do |i|
         invoice = QboInvoice.find i
         invoice_link = invoice_link + link_to( invoice.doc_number, "#{Redmine::Utils::relative_url_root}/qbo/invoice/#{i}", :target => "_blank").to_s + " "
+	invoice_link = invoice_link.html_safe
       end
     end