كتاب الْمَسَاجِدِ وَمَوَاضِعِ الصَّلاَةِ
5  
The Book of Mosques and Places of Prayer
(55)
Chapter: Making up a missed prayer. And it is recommended to hasten to make it up
(55)
باب قَضَاءِ الصَّلاَةِ الْفَائِتَةِ وَاسْتِحْبَابِ تَعْجِيلِ قَضَائِهَا ‏‏
Sahih Muslim 683

Abu Qatada reported that when the Messenger of Allah (ﷺ) was in a journey he got down for rest at night, and he used to lie down on his right side, and when he lay down for rest before the dawn, he used to stretch his forearm and place his head over his palm.

حَدَّثَنَا إِسْحَاقُ بْنُ إِبْرَاهِيمَ، أَخْبَرَنَا سُلَيْمَانُ بْنُ حَرْبٍ، حَدَّثَنَا حَمَّادُ بْنُ سَلَمَةَ، عَنْ حُمَيْدٍ، عَنْ بَكْرِ بْنِ عَبْدِ اللَّهِ، عَنْ عَبْدِ اللَّهِ بْنِ رَبَاحٍ، عَنْ أَبِي قَتَادَةَ، قَالَ كَانَ رَسُولُ اللَّهِ صلى الله عليه وسلم إِذَا كَانَ فِي سَفَرٍ فَعَرَّسَ بِلَيْلٍ اضْطَجَعَ عَلَى يَمِينِهِ وَإِذَا عَرَّسَ قُبَيْلَ الصُّبْحِ نَصَبَ ذِرَاعَهُ وَوَضَعَ رَأْسَهُ عَلَى كَفِّهِ ‏.‏
Reference : Sahih Muslim 683
In-book reference : Book 5, Hadith 398
USC-MSA web (English) reference : Book 4, Hadith 1453
  (deprecated numbering scheme)