https://ajsonline.org/article/61358-age-of-the-squantum-tillite-boston-basin-massachusetts-u-pb-zircon-constraints-on-terminal-neoproterozoic-glaciation
Age of the Squantum "Tillite," Boston Basin, Massachusetts; U-Pb Zircon Constraints on Terminal...
By M. D. Thompson, S. A. Bowring. ...