Well, the Hijri date 15 Shawwal 1411 corresponds to the Gregorian date Monday, 29 April 1991. This date lies in the tenth month of the Hijri year 1411 AH, which is Shawwal of 1411 AH. Both this Hijri and Gregorian date occur on the single day that is Monday without any doubt. The Arabic date 1411/10/15 is calculated using the Umm Al-Qura calendar and the sighting of the moon. One thing to remember is that this Arabic date may occur on different Gregorian date depending upon the region and country and obviously the moon.
If you are still not sure about the date then you can use our Arabic date converter.
The following is the conversion of the Gregorian date 29 April 1991 to its equivalent Arabic date.
The following is the conversion of the Arabic date 15 Shawwal 1411 AH to its equivalent Gregorian date.
وَجَآءُو عَلَىٰ قَمِيصِهِۦ بِدَمٍۢ كَذِبٍۢ ۚ قَالَ بَلْ سَوَّلَتْ لَكُمْ أَنفُسُكُمْ أَمْرًۭا ۖ فَصَبْرٌۭ جَمِيلٌۭ ۖ وَٱللَّهُ ٱلْمُسْتَعَانُ عَلَىٰ مَا تَصِفُونَ
And they came with false blood on his shirt. He said: Nay, but your minds have beguiled you into something. (My course is) comely patience. And Allah it is Whose help is to be sought in that (predicament) which ye describe.
Surah Yusuf(12:18)