Reed, Paul C. & Leslie Mahler, "The English Ancestry of Rebecca Farrand, Wife of John (1) Throckmorton of Providence, Rhode Island", in The American Genealogist (TAG). (Donald Lines Jacobus, et.al.) 77:110-124, 229-234 & 290-297, 2002.
Per the summary here, John's wife Rebecca Farrand was identified through the will of her sister Elizabeth Farrand.