Co-authored a paper with great repercussion that confirmed the geochronological correlation between Brazil and Africa continent

With P.M. Hurley, G.C. Melcher, U.G. Cordani, J.R. Rand, K. Kawashita, P. Vandoros, W.H. Pinson & H.W. Fairbarn. Test of continental drift by means of radiometric ages. Science 157 (3788):495-500, 1967 

HONORS  

President, International Union of Geological Sciences (1988-92)

Honorary Member, Geological Society of America (1988)

Palmes Academiques, France (1999)

Spendiarov Medal, Russian Academy of Sciences (2000)

Ingerson Lecture, International Association of Geochemistry and Cosmochemistry (2000)

Foreign Member, Academie des Sciences de L’Institut de France (2009)