Geology topics
Publications and source records attributed to H.H. Helley.
Prepared by the U.S. Geological Survey and the Arabian American Oil Company under the joint sponsorship of the Kingdom of Saudi Arabia and the U.S. Department of State.
Prepared by the U.S. Geological Survey and the Arabian American Oil Company under the joint sponsorship of the Kingdom of Saudi Arabia and the U.S. Department of State.
Prepared by the U.S. Geological Survey and the Arabian American Oil Company under the joint sponsorship of the Kingdom of Saudi Arabia and the U.S. Department of State.