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

Santorini GPS Network - PKMN-Palea Kameni Greece P.S.
Start: 02-Jul-2008
End: 22-Feb-2016
Newman, Andrew, 2008, Santorini GPS Network - PKMN-Palea Kameni Greece P.S., UNAVCO, GPS/GNSS Observations Dataset, 
https://doi.org/10.7283/T5JW8C0B