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

SAGE New Zealand GPS Network - PILK-Pilkington Glacier P.S.
Start: 03-Nov-2000
End: 09-Jun-2021
Hager, Bradford H., Herring, Thomas A., Molnar, Peter, 2001, SAGE New Zealand GPS Network - PILK-Pilkington Glacier P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5X63K64