1. ARMSTRONG, R.L., A MODEL FOR EVOLUTION OF STRONTIUM AND LEAD ISOTOPES IN A DYNAMIC EARTH, REVIEWS OF GEOPHYSICS 6: 175 (1968).
2. BENCE, A.E., TRANSACTIONS OF THE AMERICAN GEOPHYSICAL UNION 48: 251 (1967).
3. Studies of Appalachian Geology: Northern and Maritime 1968
4. BULLARD, E. C., PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY OF LONDON SERIES A-MATHEMATICAL AND PHYSICAL SCIENCES 258: 41 (1965).
5. The Geochronology of Equatorial Africa 1966