1. USDA‐ARS Remote Sensing Research Lab Bldg. 007 BARC‐West, 10300 Baltimore Ave. Beltsville MD 20705‐2350
2. NASA Goddard Space Flight Ctr. Greenbelt MD 20771
3. Dep. of Geography Univ. of Maryland College Park MD 20742
4. U.S. Army Engineer Topographic Labs Fort Belvoir VA 22060