Instrument Host Overview                                                    
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  The PUBLISHED_LITERATURE designation for INSTRUMENT_HOST is used when the   
  data presented in a given data set were collected entirely by referencing   
  results published in the literature. The data set description or product    
  labels will provide the explicit references, which in turn should provide   
  details of the original observing campaigns, data reduction, or criteria for
  inclusion for each datum reported in the PDS data set.