\begin{thebibliography}{1}

\bibitem{votech}
\url{http://www.eurovotech.org/}.

\bibitem{2000A+AS..143...33B}
F.~{Bonnarel}, P.~{Fernique}, O.~{Bienaym{\'e}}, D.~{Egret}, F.~{Genova},
  M.~{Louys}, F.~{Ochsenbein}, M.~{Wenger}, and J.~G. {Bartlett}.
\newblock {The ALADIN interactive sky atlas. A reference tool for
  identification of astronomical sources}.
\newblock {\em A\&AS}, 143:33--40, April 2000.

\bibitem{2007HiA....14..622B}
U.~{Becciani}, M.~{Comparato}, A.~{Costa}, C.~{Gheller}, B.~{Larsson},
  F.~{Pasian}, and R.~{Smareglia}.
\newblock {VisIVO: an interoperable visualisation tool for Virtual Observatory
  data}.
\newblock {\em Highlights of Astronomy}, 14:622--622, 2007.

\bibitem{xpa}
\url{http://hea-www.harvard.edu/RD/xpa/}.

\bibitem{plastic}
J.~{Taylor}, T.~{Boch}, M.~{Comparato}, M.~{Taylor}, and N.~{Winstanley}.
\newblock {PLASTIC --- a protocol for desktop application interoperability}.
\newblock \url{http://ivoa.net/Documents/latest/PlasticDesktopInterop.html},
  June 2006.
\newblock IVOA note.

\bibitem{plastic-sf}
\url{http://plastic.sourceforge.net/}.

\bibitem{xmlrpc}
\url{http://www.xmlrpc.com/}.

\bibitem{docstd}
R.~J.~Hanisch et al.
\newblock {IVOA Document Standards}.
\newblock \url{http://www.ivoa.net/Documents/latest/DocStd.html}, 2003.
\newblock IVOA Recommendation.

\end{thebibliography}