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

Greenland GNSS Network - KULU-Kulusuk P.S.
Start: 28-Jun-1996
End: 31-Dec-2011
Larson, Kristine, Van Dam, Tonie M., 1998, Greenland GNSS Network - KULU-Kulusuk P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5NZ85QW

Greenland GNSS Network - KULU-Kulusuk P.S.
Start: 28-Jun-1996
End: 13-Aug-2019
SDFE, The Danish Agency, UNAVCO Community, Larson, Kristine, Van Dam, Tonie M., 1998, Greenland GNSS Network - KULU-Kulusuk P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/MF3E-KV11

Greenland GNSS Network - KULU-Kulusuk P.S.
Start: 01-Jan-2019
End: 13-Aug-2019
SDFE, The Danish Agency, 1998, Greenland GNSS Network - KULU-Kulusuk P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/GW1W-KR05

Greenland GNSS Network - KULU-Kulusuk P.S.
Start: 01-Jan-2012
End: 31-Dec-2018
UNAVCO Community, 1998, Greenland GNSS Network - KULU-Kulusuk P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/54X4-2Z10