Question:
Who was the head of Cologne in Sep, 1993?

Context:
 Ernst Schwering is the head of the government of Cologne from Nov, 1951 to Nov, 1956. 
 John van Nes Ziegler is the head of the government of Cologne from Dec, 1973 to Oct, 1980. 
 Jürgen Roters is the head of the government of Cologne from Oct, 2009 to Oct, 2015. 
 Fritz Schramma is the head of the government of Cologne from Sep, 2000 to Oct, 2009. 
 Theo Burauen is the head of the government of Cologne from Nov, 1956 to Dec, 1973. 
 Henriette Reker is the head of the government of Cologne from Oct, 2015 to Dec, 2022. 
 Norbert Burger is the head of the government of Cologne from Oct, 1980 to Sep, 1999. 
 Robert Görlinger is the head of the government of Cologne from Nov, 1950 to Nov, 1951.

Answer:
Question:
Who was the head of Cologne in Sep, 1993?

Context:
 Ernst Schwering is the head of the government of Cologne from Nov, 1951 to Nov, 1956. 
 John van Nes Ziegler is the head of the government of Cologne from Dec, 1973 to Oct, 1980. 
 Jürgen Roters is the head of the government of Cologne from Oct, 2009 to Oct, 2015. 
 Fritz Schramma is the head of the government of Cologne from Sep, 2000 to Oct, 2009. 
 Theo Burauen is the head of the government of Cologne from Nov, 1956 to Dec, 1973. 
 Henriette Reker is the head of the government of Cologne from Oct, 2015 to Dec, 2022. 
 Norbert Burger is the head of the government of Cologne from Oct, 1980 to Sep, 1999. 
 Robert Görlinger is the head of the government of Cologne from Nov, 1950 to Nov, 1951.

Answer:
user
Norbert Burger
assistant
Question:
Who was the head of Cologne in Sep, 1993?

Context:
 Ernst Schwering is the head of the government of Cologne from Nov, 1951 to Nov, 1956. 
 John van Nes Ziegler is the head of the government of Cologne from Dec, 1973 to Oct, 1980. 
 Jürgen Roters is the head of the government of Cologne from Oct, 2009 to Oct, 2015. 
 Fritz Schramma is the head of the government of Cologne from Sep, 2000 to Oct, 2009. 
 Theo Burauen is the head of the government of Cologne from Nov, 1956 to Dec, 1973. 
 Henriette Reker is the head of the government of Cologne from Oct, 2015 to Dec, 2022. 
 Norbert Burger is the head of the government of Cologne from Oct, 1980 to Sep, 1999. 
 Robert Görlinger is the head of the government of Cologne from Nov, 1950 to Nov, 1951.

Answer:
user
Ernst Schwering
John van Nes Ziegler
Fritz Schramma
Jürgen Roters
Theo Burauen
Henriette Reker
Robert Görlinger
assistant
Question:
Who was the head of Cologne in Sep, 1993?

Context:
 Ernst Schwering is the head of the government of Cologne from Nov, 1951 to Nov, 1956. 
 John van Nes Ziegler is the head of the government of Cologne from Dec, 1973 to Oct, 1980. 
 Jürgen Roters is the head of the government of Cologne from Oct, 2009 to Oct, 2015. 
 Fritz Schramma is the head of the government of Cologne from Sep, 2000 to Oct, 2009. 
 Theo Burauen is the head of the government of Cologne from Nov, 1956 to Dec, 1973. 
 Henriette Reker is the head of the government of Cologne from Oct, 2015 to Dec, 2022. 
 Norbert Burger is the head of the government of Cologne from Oct, 1980 to Sep, 1999. 
 Robert Görlinger is the head of the government of Cologne from Nov, 1950 to Nov, 1951.

Answer:
user
Norbert Burger
assistant