Question:
Who was the head of Mons in Nov, 1973?

Context:
 Leo Collard is the head of the government of Mons from Jan, 1972 to Jan, 1974. 
 Abel Dubois is the head of the government of Mons from Jan, 1974 to Jan, 1989. 
 Maurice Lafosse is the head of the government of Mons from Jan, 1989 to Jan, 2001. 
 Elio Di Rupo is the head of the government of Mons from Jan, 2001 to Dec, 2018.

Answer:
Leo Collard