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

Montserrat GPS Network - MVO1-Montserrat Volcano Obs. New P.S.
Start: 20-Feb-1998
End: 18-Oct-1999
Mattioli, Glen, 2000, Montserrat GPS Network - MVO1-Montserrat Volcano Obs. New P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5P26WG1