“But why do you not cease to call Mary the mother of God, if Isaiah nowhere says that he that is born of the virgin is the "only begotten Son of God" and "the firstborn of all creation?"”

Calvin to the Foreigners’ Church in London, 1552-10-27, in George Cornelius Gorham, Gleanings of a few scattered ears, during the period of Reformation in England and of the times immediately succeeding : A.D. 1533 to A.D. 1588 http://books.google.com/books?vid=0bbTMcT6wXFWRHGP&id=esICAAAAQAAJ&printsec=titlepage&dq=%22george+cornelius+gorham%22 (London: Bell and Daldy, 1857), p. 285.

New Testament Commentaries, John 1.32; as quoted in Thomas F. Torrance, "A Harmony of Matthew, Mark and Luke” https://books.google.com/books/about/A_harmony_of_the_Gospels_Matthew_Mark_an.html?id=0diPvgAACAAJ (St. Andrew's Press, Edinburgh, 1972), p.32. and "The Gospel of St. John: The Story of the Son of God" https://books.google.com/books?isbn=113704120X
St John
Variant: And at this day, the blessedness brought to us by Christ cannot be the subject of our praise, without reminding us, at the same time, of the distinguished honor which God was pleased to bestow on Mary, in making her the mother of his Only Begotten Son.

John Calvin, https://books.google.com/books?isbn=1556352468 Epistle CCC to the French church in London, 27th September 1552; translated by Jules Bonnet, p.362

Weimar edition of Martin Luther's Works, English translation edited by J. Pelikan [Concordia: St. Louis], Vol. 11, Vol. 24, 107

John Calvin. "Commentary on Luke 1:43". Harmony of Matthew, Mark, and Luke. 1. Retrieved 2009-01-07.
Harmony of Matthew, Mark, Luke

XI, 9
The City of God (early 400s)
Context: For when God said, “Let there be light, and there was light,” if we are justified in understanding in this light the creation of the angels, then certainly they were created partakers of the eternal light which is the unchangeable Wisdom of God, by which all things were made, and whom we call the only-begotten Son of God; so that they, being illumined by the Light that created them, might themselves become light and be called “Day,” in participation of that unchangeable Light and Day which is the Word of God, by whom both themselves and all else were made. “The true Light, which lighteth every man that cometh into the world,” — this Light lighteth also every pure angel, that he may be light not in himself, but in God; from whom if an angel turn away, he becomes impure, as are all those who are called unclean spirits, and are no longer light in the Lord, but darkness in themselves, being deprived of the participation of Light eternal. For evil has no positive nature; but the loss of good has received the name “evil.”

The Second Coming of Christ: The Resurrection of the Christ Within You, (2004) by Yogananda

Zwingli Opera, Corpus Reformatorum, Volume 1, p. 424.