In the United States, Perry Mason was created in 1933. Books published between 1929 and 1978 are protected for from their publication date, provided their copyrights were renewed.

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The Internet Archive (archive.org) is a non-profit digital library. While they sometimes face legal challenges regarding modern books, they host a vast collection of older scanned books. They operate on a "controlled digital lending" model, meaning you have to "borrow" the digital book for a set period, similar to a physical library. This is a safer and more ethical way to access older editions that may be out of print.