More International Law Trivia

Following my posts (here and here) about elections to the International Court of Justice of judges who had previously been on another international tribunal, I have another question for readers. Giorgio Gaja who was elected to the ICJ last month (see here) is currently an ad hoc  judge in the Jurisdictional Immunities of the State (Germany v. Italy: Greece intervening) case. He had also been ad hoc judge in three previous ICJ cases. The question is:

Which judges of the ICJ had served as ad hoc judges at the ICJ prior to their election to the ICJ?

Note that I am asking for ICJ judges who were appointed ad hoc judges before they became full time judges on the ICJ. I am excluding those ad hoc judges who were appointed as such after they had been ICJ judges. There are many in the latter category. Gilbert Guillaume, former ICJ president is currently an ad hoc judges in three cases now before the Court. Judge Sir Robert Jennings was ad hoc Judge in the Lockerbie case after leaving the court. Judges Keba Mbaye, Ajibola, Sette-Camara, Ruda and others were also ad hoc judges after leaving the ICJ.