OPEC siege members of OPEC were taken hostage in Vienna, Austria, where the ministers were attending a meeting at the OPEC headquarters at Dr-Karl-Lueger-Ring 10 (renamed Universitätsring in 2012). The hostage attack was orchestrated by a six-person team led by Venezuelan terrorist Carlos the Jackal (which included Gabriele Kröcher-Tiedemann, Hans-Joachim Klein and Anis al-Naqqash). The self-named "Arm of the Arab Revolution" group called for the liberation of Palestine. Carlos planned to take over the conference by force and kidnap all eleven oil ministers in attendance and hold them for ransom, with the exception of Ahmed Zaki Yamani and Iran's Jamshid Amuzegar, who
Damp (structural) in the underlying ground would appear to be sound, there is little data to suggest that it is effective in practice. Indeed, G and I Massari stated in the ICCROM publication "Damp Buildings Old and New" that little effect was observed with "open trenching" and no effect was observed with "covered trenching." These attempt to control rising damp through the phenomenon of electro osmosis. Whilst there is evidence to suggest that these systems can be useful in moving salts in walls there is little in the way of independent data to demonstrate effectiveness in treating rising damp. The BRE publication