In dd/mm/yyy format: I. X. MCMXCI.
10 10 1991 in Roman numerals is X X MCMXCI.
10: X 01: I 1950: MCML
The date 10-19-1991 in Roman numberals would be X.XIX.MCMXCI
I X MCMLXXXV
I X MCMLXXXV
I-X-XCVIII
In today's terms 03 10 1991 converted into Roman numerals is III-X-MCMXCI. But during the times of the Romans they would have probably wrote out 1991 as MDCCCCLXXXXI.
In todays notation of Roman numerals: XII-XV-MCMXCI The ancient Romans probably wrote out 1991 simply as XMMI (2001-10)
X-XXIV-MCMXCI
X - iv - mcmxci
X-XXI-MCMXCI
V-X-MCMXCI