UNAVCO has implemented DOI publication for GPS/GNSS datasets. UNAVCO publishes (assigns DOIs) for four different data set types, all with associated GPS/GNSS data that have been archived to certain quality standards. The types are GPS/GNSS Campaign Data Sets; GPS/GNSS Continuous Station Data Sets; Aggregated Data Sets; and Composite Data Sets. The first two are considered primary data set types. The third and fourth types are derived or secondary data set types because they are composed of two or more data sets of the primary type.