in graphite, lower right: 3/150 Dennis Oppenheim 1978; text printed in black across center of sheet: 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 in black, lower right verso: © George T. Boris
Gift to NGA in 2016 by Bob Stana and Tom Judy, Washington, DC.