lower right in graphite: 3/150 Dennis Oppenheim 1978
text on plate: Time Line. 1968. Boundary between USA/Canada; St. John River; Fort Kent, Maine. 1" x 3" x 3' mile cut between the two countries.
Marks and Labels
stamped lower right verso in black: © George T. Boris
Bob Stana and Tom Judy, Washington, DC; acquired 2016 by the National Gallery of Art