The FDSN StationXML schema and related documents are maintained by the International Federation of Digital Seismograph Networks (FDSN).
StationXML is a schema definition for representing the Standard for the Exchange of Earthquake (SEED) metadata in XML.
SEED and StationXML are maintained by FDSN Working Group II.
Approved releases are available from http://www.fdsn.org/xml/station/.