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

Arctic PI Continuous - GLS2-GLISN 2 P.S.
Start: 07-Jun-2011
End: 10-Sep-2021
Detrick, Robert, Anderson, Kent, 2012, Arctic PI Continuous - GLS2-GLISN 2 P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5S46Q3N