The Book of Prayer - Travellers
6/16. Chapter:
It is permissible to offer voluntary prayers standing or sitting, and to stand and sit in the same rak`ah
Sahih Muslim
وَحَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا كَهْمَسٌ، عَنْ عَبْدِ اللَّهِ بْنِ شَقِيقٍ، قَالَ قُلْتُ لِعَائِشَةَ . فَذَكَرَ عَنِ النَّبِيِّ صلى الله عليه وسلم بِمِثْلِهِ .
'Abdullah b. Shaqiq reported: I said to 'A'isha and she made a mention of that (recorded above) about the Messenger of Allah (ﷺ).
Reference : Sahih Muslim 732bIn-book reference : Book 6, Hadith 139USC-MSA web (English) reference : Book 4, Hadith 1594