Publicity photo of the <i>I Love Lucy</i> cast: William Frawley (Fred Mertz), Desi Arnaz (Ricky Ricardo), Vivian Vance (Ethel Mertz), Lucille Ball  (Lucy Ricardo).
CBS Television-see above re: advertising and publicity agencies and how they were used for publicity material distribution.
The press release is not dated.  The Lucy-Desi Comedy Hour aired on CBS from 1962 to 1967.  It should also be noted that the press release is from a public relations agency; this method of distributing publicity materials was common for networks, studios and program sponsors in the 1950s and 1960s.  <a class="external text" href="https://upload.wikimedia.org/wikipedia/commons/archive/f/f0/20111002165155%21Abby_Dalton_Hennessey_wedding1962.JPG">one example from 1962</a>.  The addresses given for the East and West Coast offices of the public relations agencies include a zone number, not a Zip Code, which began being used in 1963.  Prior to this, large cities used zone numbers in their addresses.  The telephone numbers listed do not include area codes and they are listed with letter prefixes, which were converted to all numerals well over 20 years ago.  The photo has only a "date use" stamp for 27 April 1989, which is the day after Lucille Ball's death.  The photo was apparently kept in the newspaper's photo files after it was received and not published in that respective newspaper until after Ball's death.  Have seen re-issued photos of other subjects and note that the publicity information on them is not the original, but has been updated, and that the re-issues are copyrighted and carry notices to that effect. This was sent circa 1960s but kept on file for many years.
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