The following information obtained from UNAVCO's online DOI system:
(https://www.unavco.org/data/doi/search/search.html)

Central Andean Tectonic Observatory Geodetic Array - CLLA-Challacolla P.S.
Start: 01-Aug-2008
End: 31-Dec-2014
Simons, Mark, Galetzka, John E., Genrich, Jeff F., Ortega, Francisco, Comte, Diana, Glass, Bianca, Gonzalez, Gabriel, 2010, Central Andean Tectonic Observatory Geodetic Array - CLLA-Challacolla P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5JM27N5