Geoforschungszentrum Potsdam Telegrafenberg A 17 D-1561 Potsdam GERMANY =========================== FOLLOWING PSMSL DOCUMENTATION ADDED 09-Jul-1992 THE GEOFORSCHUNGSZENTRUM POTSDAM WAS FORMALLY KNOWN AS THE CENTRAL INSTITUTE FOR THE PHYSICS OF THE EARTH (ZIPE) AND PREVIOUS TO THAT AS THE GEODAETISCHES INSTITUT POTSDAM.