Original: Sir John Robert Kerr , AK , GCMG , GCVO , QC ( 24 September 1914 24 March 1991 ) was the 13th Chief Justice of the Supreme Court of New South Wales and 18th Governor-General of Australia .
Simplified: Sir John Robert Kerr ( 24 September 1914 -- 24 March 1991 ) was the 18th Governor-General of Australia .