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 *                                                                            *
 *            THE OBSERVATIONS FILE FORMAT SPECIFICATION                      *
 *                                                                            *
 *    The source of the observations file format specification must be one of *
 *    the following:                                                          *
 *                                                                            *
 *    observations - the observations file written by (MK*)OBSFILE            *
 *         catalog - a catalog written by MKCATALOG                           *
 *           STDIN - the standard input                                       *
 *        filename - a user supplied file                                     *
 *                                                                            *
 *    Note that the MKCATALOG task can be used to type in a set of            *
 *    observations, although it is more usually used to type in standard star *
 *    data.                                                                   *
 *                                                                            *
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