Section 6,3: FORTRAN_77_Standard

 The character set specified by the FORTRAN-77 Standard consists of
 the uppercase letters A through Z, the digits 0 through 9, and the
 following special characters:

    SP   (space)                ,    (comma)
    $    (dollar sign)          -    (minus sign)
    '    (apostrophe)           .    (period)
    (    (left parenthesis)     /    (slash)
    )    (right parenthesis)    :    (colon)
    *    (asterisk)             =    (equal sign)
    +    (plus sign)