VMS Help DSR, DSR Flags, Bold  *Conan The Librarian (sorry for the slow response - running on an old VAX)

    The single character occurrence of the Bold flag (*) causes
    the next character to be printed in boldface; that is, to be
    overstruck once. You can cause characters to be overstruck more
    than once by using the /BOLD=number qualifier when processing
    the file with the RUNOFF command. Pairing the bold flag with the
    uppercase flag (^*) turns on the bolding until the lowercase/bold
    pair (\*) is encountered.

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