/** three_letter_month( ?IntIdx, -Month ).

Indexes numeric month to 3 letter atom.

@author nicos angelopoulos
@version  0.1 2010/10/7

*/
three_letter_month( 1, 'Jan').
three_letter_month( 2, 'Feb').
three_letter_month( 3, 'Mar').
three_letter_month( 4, 'Apr').
three_letter_month( 5, 'May').
three_letter_month( 6, 'Jun').
three_letter_month( 7, 'Jul').
three_letter_month( 8, 'Aug').
three_letter_month( 9, 'Sep').
three_letter_month(10, 'Oct').
three_letter_month(11, 'Nov').
three_letter_month(12, 'Dec').