Peter M. LeTourneau is an associate research scientist at the Lamont-Doherty Earth Observatory of Columbia University. Paul E. Olsen is A.D. Storke Memorial Professor of Earth and Environmental Sciences at the Lamont-Doherty Earth Observatory of Columbia University.
<p> represent a comprehensive overview of up-to-date knowledge...they are worthy complements to earlier compilations -- Mark Tomasso, Palaeontological Newsletter