He served as the Parliamentary leader of the Christian Historical Union in the Senate from December 10 , 1968 until June 8 , 1977 when the Christian Historical Union merged into the Christian Democratic Appeal , he became the first Parliamentary leader of the Christian Democratic Appeal in the Senate serving until June 10 , 1981 .
He served as the Parliamentary leader of the Christian Historical Union in the Senate from December 10 , 1968 until June 8 , 1977 when the Christian Historical Union merged into the Christian Democratic Appeal .