#missive__letter  a written message addressed to a person or organization; "wrote an indignant letter to the editor"
  supertype:  textual_matter__textualmatter__text  the words of something written; "there were more than a thousand words of text"; "they handed out the printed text of the mayor's speech"; "he wants to reconstruct the original text"
  subtype:  business_letter  covering_letter  crank_letter  encyclical_letter  personal_letter  form_letter  open_letter  chain_letter  pastoral.missive  round_robin  airmail_letter  epistle  dead_letter  letter_of_intent
  part:  postscript  name_and_address
  part of:  mail  the bags of letters and packages that are transported by the postal service
  part of:  correspondence  communication by the exchange of letters

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