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

Greenland GNSS Network - KULL-Kullorsuaq P.S.
Start: 01-Jan-2012
End: 31-Dec-2018
UNAVCO Community, 2007, Greenland GNSS Network - KULL-Kullorsuaq P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/DZJM-M959

Greenland GNSS Network - KULL-Kullorsuaq P.S.
Start: 01-Jan-2019
End: 19-May-2019
SDFE, The Danish Agency, 2007, Greenland GNSS Network - KULL-Kullorsuaq P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/AVG7-D967

Greenland GNSS Network - KULL-Kullorsuaq P.S.
Start: 15-Aug-2007
End: 31-Dec-2011
Bevis, Michael, 2007, Greenland GNSS Network - KULL-Kullorsuaq P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T53T9F8D

Greenland GNSS Network - KULL-Kullorsuaq P.S.
Start: 15-Aug-2007
End: 19-May-2019
SDFE, The Danish Agency, UNAVCO Community, Bevis, Michael, 2007, Greenland GNSS Network - KULL-Kullorsuaq P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/YE6K-VR40