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

PBO GPS Network - P292-LowGastro_CN2008 P.S.
Start: 08-Feb-2008
End: 21-Sep-2020
UNAVCO Community, 2008, PBO GPS Network - P292-LowGastro_CN2008 P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5WM1BD0