\def\endate#1#2{%
    \ifcase#1%            Translate month number to name
        \or January %
        \or February %
        \or March %
        \or April %
        \or May %
        \or June %
        \or July %
        \or August %
        \or September %
        \or October %
        \or November %
        \or December %
    \fi%
    #2%                   Print day number
    \raise 1bp%           Raise the superscript by 1bp
    \hbox{%               Box to contain superscript
        \ifcase#2%        Output the correct superscript:
            \or st%        1st
            \or nd%        2nd
            \or rd%        3rd
            \or th%        4th
            \or th%        5th
            \or th%        6th
            \or th%        7th
            \or th%        8th
            \or th%        9th
            \or th%       10th
            \or th%       11th
            \or th%       12th
            \or th%       13th
            \or th%       14th
            \or th%       15th
            \or th%       16th
            \or th%       17th
            \or th%       18th
            \or th%       19th
            \or th%       20th
            \or st%       21st
            \or nd%       22nd
            \or rd%       23rd
            \or th%       24th
            \or th%       25th
            \or th%       26th
            \or th%       27th
            \or th%       28th
            \or th%       29th
            \or th%       30th
            \or st%       31st
        \fi%
    }%
}