Who was the father of James the Less and Joses?

This is one of the most difficult questions in the Gospel history, and still being debated.

Matthew (13, 55) and Mark (6, 3) declare them to be sons of the Virgin Mary and brothers of Jesus. Paul (Gal. 1, 19) affirms that James was the brother of Jesus.

If they were sons of the Virgin Mary, Joseph must have been their father. But Matthew (10, 3) and Mark (3, 18) state that James the Less was "the son of Alpheus." According to John (compare John 19, 25 with Matthew 28, 56) Cleophas was their father.