Question:
Which team did Theo Bücker play for in Apr, 1974?

Context:
 Theo Bücker plays for MSV Duisburg from Jan, 1973 to Jan, 1978. 
 Theo Bücker plays for Al Ittihad FC from Jan, 1978 to Jan, 1981. 
 Theo Bücker plays for FC Schalke 04 from Jan, 1981 to Jan, 1984. 
 Theo Bücker plays for Borussia Dortmund from Jan, 1969 to Jan, 1973.

Answer:
MSV Duisburg