ENOfficial
'A’isha said (may Allah be well pleased with her): “Allah’s Messenger (Allah bless him and give him peace) used to perform eleven cycles of ritual prayer during the night, making one of them odd-numbered , and when he had finished, he would recline on his right side.”
Source: sunnah.com
Other translations
Arabic
حَدَّثَنَا إِسْحَاقُ بْنُ مُوسَى، قَالَ: حَدَّثَنَا مَعْنٌ، قَالَ: حَدَّثَنَا مَالِكٌ، عَنِ ابْنِ شِهَابٍ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ: أَنَّ رَسُولَ اللهِ صلى الله عليه وسلم، كَانَ يُصَلِّي مِنَ اللَّيْلِ إِحْدَى عَشْرَةَ رَكْعَةً، يُوتِرُ مِنْهَا بِوَاحِدَةٍ، فَإِذَا فَرَغَ مِنْهَا، اضْطَجَعَ عَلَى شِقِّهِ الأَيْمَنِ.
sunnah.com