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

Yellowstone Hotspot GPS Network - BLW2-Boulder Wyoming P.S.
Start: 02-Sep-2003
End: 13-Apr-2006
Smith, Robert B., 2003, Yellowstone Hotspot GPS Network - BLW2-Boulder Wyoming P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5S46Q8W

Yellowstone Hotspot GPS Network - BLW2-Boulder Wyoming P.S.
Start: 13-Apr-2006
End: 14-Nov-2022
UNAVCO Community, 2003, Yellowstone Hotspot GPS Network - BLW2-Boulder Wyoming P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5NC5ZHQ

Yellowstone Hotspot GPS Network - BLW2-Boulder Wyoming P.S.
Start: 02-Sep-2003
End: 14-Nov-2022
UNAVCO Community, Smith, Robert B., 2003, Yellowstone Hotspot GPS Network - BLW2-Boulder Wyoming P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5WW7G09