You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Pope_Paul_VI

Context:
Between the third and fourth sessions the pope announced reforms in the areas of Roman Curia, revision of Canon Law, regulations for mixed marriages involving several faiths, and birth control issues. He opened the final session of the council, concelebrating with bishops from countries where the Church was persecuted. Several texts proposed for his approval had to be changed. But all texts were finally agreed upon. The Council was concluded on 8 December 1965, the Feast of the Immaculate Conception.

Question:
In what year was Paul Vi's final counsel session?

1965