This page, posted October 23, 2000, lists equations for transforming ITRF97 positional coordinates (XI, YI, ZI) at a specified epoch date (denoted t) to their corresponding NAD 83 values (XN, YN, ZN) at this same epoch date and gives a short explanation with hypertext references. Both the United States' National Geodetic Survey and Canada's Geodetic Survey Division have adopted the equations.