Question: What is a resort and National Historic Landmark in Palm Beach, Florida, built from 1924 to 1927 by cereal-company heiress and socialite Marjorie Merriweather Post, that has Magazines available for free to members of the resort?
Sentence (from "Mystery on Fifth Avenue"): It was done without his clients' knowledge, and they did not discover the mystery until several months after moving in.
Relevant evidence: No