diff --git a/tea.h b/tea.h
index 5bc2a562..973486a9 100644
--- a/tea.h
+++ b/tea.h
@@ -115,7 +115,8 @@ struct BTEA_Info : public FixedKeyLength<16>
 
 /// \brief BTEA block cipher
 /// \details Corrected Block TEA as described in "xxtea". This class hasn't been tested yet.
-/// \sa <a href="http://www.cryptopp.com/wiki/TEA">Corrected Block TEA</a>.
+/// \sa <A HREF="http://www.movable-type.co.uk/scripts/xxtea.pdf">Correction to xtea</A> and
+///   <a href="http://www.cryptopp.com/wiki/TEA">Corrected Block TEA</a>.
 class BTEA : public BTEA_Info, public BlockCipherDocumentation
 {
 	/// \brief BTEA block cipher default operation