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

COCONet GPS Network - CN33-PenenomeUPCR2011 P.S.
Start: 11-Nov-2011
End: 04-Apr-2018
UNAVCO Community, 2011, COCONet GPS Network - CN33-PenenomeUPCR2011 P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T53X84Z9