Data Set Overview
      =================
      A comprehensive compilation of asteroid-related references,
      produced by Clifford Cunningham (1990) as the 'Minor Planet Index
      to Scientific Papers [CUNNINGHAM1990]. This version of the
      database contains 12,769 citations from the period 1621-1993.
 
 
      Modification History
      ====================
      In 2000, a review of the data file revealed several typographical
      errors (specifically, period characters which should have been
      commas), some field alignment problems at the end of the file,
      and four missing publication dates. The typographical errors and
      alignments were corrected. The publication dates for citations
      number 6971, 9468, 10046 and 10109 were found and entered into
      the appropriate place in the file.  At the same time, the label
      file DESCRIPTION fields were expanded and some inconsistencies
      in the use of blanks in the asteroid list field were eliminated.
      A blank space was inserted between fields that otherwise abutted
      in the data file. The main data file was then sorted on REFERENCE
      CODE.
 
      A file cross-indexing cited objects to references was generated
      programmatically, sorted on object number, labelled and added to
      the dataset.
 
      Note that no additional citations were added to the file.
 
      At this time the files and dataset directory were renamed from
      'refs' to 'mpisp' (Minor Planet Index to Scientific Papers)
      because of the constant confusion caused by having a dataset
      called 'refs' parallel to system reference data.

This data set covers references published between 1621 and 1993,
      and does not claim completeness during that period.
 
      This version of the data set underwent external peer review on
      May 10, 2002.