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

COCONet GPS Network - CN01-Bethesda_ANT2015 P.S.
Start: 28-Jan-2015
End: 17-Jul-2019
UNAVCO Community, 2015, COCONet GPS Network - CN01-Bethesda_ANT2015 P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T57P8WPN