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Othen v. Roster was authored by Justice Brewster of the Texas Supreme Court.
Here a map of the property at issue in Othen, courtesy of the Dukeminier web site.
Here is a map of the Atlantis Beach Club from the New Jersey Supreme Court case, and a contemporary article from the New York Times. Also, here is a listing of the current fees to use the beach (assuming you can find it).
You can also learn about a recent Texas Supreme Court opinion, Severance v. Patterson, concerning easements on the beach of the Gulf Coast here and here.