When using the tide gauge data set from the PSMSL, we ask that you reference the last paper describing the data set, as well as the data set itself. As an example, "the tide gauge data [Holgate et al., 2013; PSMSL, 2014] show that ..."
Permanent Service for Mean Sea Level (PSMSL), 2014, "Tide Gauge Data",
Retrieved 21 Jul 2014 from http://www.psmsl.org/data/obtaining/.
Simon J. Holgate, Andrew Matthews, Philip L. Woodworth, Lesley J. Rickards, Mark E. Tamisiea, Elizabeth Bradshaw, Peter R. Foden, Kathleen M. Gordon, Svetlana Jevrejeva, and Jeff Pugh (2013) New Data Systems and Products at the Permanent Service for Mean Sea Level. Journal of Coastal Research: Volume 29, Issue 3: pp. 493 – 504. doi:10.2112/JCOASTRES-D-12-00175.1.
Note above that the "Retrieved" date above should correspond to the "Extracted from Database" date on the data page. This date and advice is also distributed in the zip files that contain the whole data set. While bibliographic requirements will vary from journal to journal, we believe that is important to include the "Extracted from Database" date.