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

Yellowstone Caldera GPS Network - HVWY-Hayden Valley P.S.
Start: 10-Sep-2004
End: 14-Nov-2022
UNAVCO Community, 2001, Yellowstone Caldera GPS Network - HVWY-Hayden Valley P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5R49P32

Yellowstone Caldera GPS Network - HVWY-Hayden Valley P.S.
Start: 01-Jul-2001
End: 14-Nov-2022
UNAVCO Community, Smith, Robert B., 2001, Yellowstone Caldera GPS Network - HVWY-Hayden Valley P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5GQ6W3S

Yellowstone Caldera GPS Network - HVWY-Hayden Valley P.S.
Start: 01-Jul-2001
End: 10-Sep-2004
Smith, Robert B., 2001, Yellowstone Caldera GPS Network - HVWY-Hayden Valley P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5MC8XCB