1. Formerly Instituto Mexicano del Petróleo, Eje Central Lázaro Cárdenas Norte 152, Col. San Bartolo Atepehuacan C.P. 07730, Ciudad de México, México; presently TU Delft, Building 23, Stevinweg 1/PO-box 5048, CN Delft 2628, The Netherlands..
2. Columbia University, Lamont-Doherty Earth Observatory, 61 Route 9W, Palisades, New York 10964-8000, USA..
3. TU Delft, Building 23, Stevinweg 1/PO-box 5048, CN Delft 2628, The Netherlands..