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 [Woodworth and Player, 2003; PSMSL, 2013] show that ..."
Permanent Service for Mean Sea Level (PSMSL), 2013, "Tide Gauge Data",
Retrieved 15 May 2013 from http://www.psmsl.org/data/obtaining/.
Woodworth, P.L. and R. Player, 2003. The Permanent Service for Mean Sea Level: an update to the 21st century. Journal of Coastal Research, 19, 287-295.
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.