William Knowlton, Jr. married Elizabeth Ann Balch at Ipswich, Essex County, Massachusetts. They were my 10th great grandparents. The marriage is recorded in "New England Marriages Prior to 1700", as follows: (Entry outlined in yellow)
New England Marriages Prior to 1700, by Clarence Almon Torrey, Genealogical Pub. Co, 2012, p. 446.