Question:
Who was the owner of Nocturne: Blue and Silver – Chelsea in Jan, 1972?

Context:
 Nocturne: Blue and Silver – Chelsea is owned by Miss Rachel and Miss Jean Alexander from Jan, 1916 to Jan, 1959. 
 Nocturne: Blue and Silver – Chelsea is owned by National Gallery from Jan, 1959 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by Tate from Jan, 1972 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by William Cleverley Alexander from Jan, 1871 to Jan, 1916.

Answer:
Question:
Who was the owner of Nocturne: Blue and Silver – Chelsea in Jan, 1972?

Context:
 Nocturne: Blue and Silver – Chelsea is owned by Miss Rachel and Miss Jean Alexander from Jan, 1916 to Jan, 1959. 
 Nocturne: Blue and Silver – Chelsea is owned by National Gallery from Jan, 1959 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by Tate from Jan, 1972 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by William Cleverley Alexander from Jan, 1871 to Jan, 1916.

Answer:
user
Tate
assistant
Question:
Who was the owner of Nocturne: Blue and Silver – Chelsea in Jan, 1972?

Context:
 Nocturne: Blue and Silver – Chelsea is owned by Miss Rachel and Miss Jean Alexander from Jan, 1916 to Jan, 1959. 
 Nocturne: Blue and Silver – Chelsea is owned by National Gallery from Jan, 1959 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by Tate from Jan, 1972 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by William Cleverley Alexander from Jan, 1871 to Jan, 1916.

Answer:
user
William Cleverley Alexander
Miss Rachel and Miss Jean Alexander
William Cleverley Alexander
Miss Rachel and Miss Jean Alexander
assistant
Question:
Who was the owner of Nocturne: Blue and Silver – Chelsea in Jan, 1972?

Context:
 Nocturne: Blue and Silver – Chelsea is owned by Miss Rachel and Miss Jean Alexander from Jan, 1916 to Jan, 1959. 
 Nocturne: Blue and Silver – Chelsea is owned by National Gallery from Jan, 1959 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by Tate from Jan, 1972 to Jan, 1972. 
 Nocturne: Blue and Silver – Chelsea is owned by William Cleverley Alexander from Jan, 1871 to Jan, 1916.

Answer:
user
Tate
assistant