December is the twelth month and would be XII. The 19th is represented by XIX. And the year would be MMXI. So it would normally be shown as XII-XIX-MMXI.
XXII.XII.MMXI
It is: XII-XXV-MMXI
It is: XII-XV-MMXI
It is: 12-1-2011 = XII-I-MMXI
2011 = MMXI
December 21, 2011 is written as "XII XXI MMXI" in Roman numerals.
2011 = MMXI
MMXI
May 6, 2011 in Roman numerals is V VI MMXI
The Roman numerals of MMXII are equivalent to 2011 in today's numbers
IX.VII.MMXI
IV.V.MMXI