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

Africa Array GPS Network - VHMR-Vohemar P.S.
Start: 26-Oct-2012
End: 16-Feb-2017
Nyblade, Andy, 2012, Africa Array GPS Network - VHMR-Vohemar P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5416V4T