Jami` at-Tirmidhi 2129 b
Sufyan bin 'Uyainah reported this Hadith from Az-Zuhri, from 'Urwah, from 'Aishah and he added in it:
"Dont you see that the Mujazziz passed by Zaid bin Harithah and Usamah bin Zaid while their heads were covered, and their feet were exposed, and he said: 'These feet belong to each other.'"
This is how Sa'eed bin Abdur-Rahman - and more than one narrator - narrated this Hadith from Sufyan bin 'Uyanah, from Az-Zuhri, from 'Urwah, from A'ishah. And this Hadith is Hasan Sahih. 
Some of the people of knowledge used this Hadith to support the case of Qa'if.
وَقَدْ رَوَى ابْنُ عُيَيْنَةَ، هَذَا الْحَدِيثَ عَنِ الزُّهْرِيِّ، عَنْ عُرْوَةَ، عَنْ عَائِشَةَ، وَزَادَ، فِيهِ ‏
"‏ أَلَمْ تَرَىْ أَنَّ مُجَزِّزًا مَرَّ عَلَى زَيْدِ بْنِ حَارِثَةَ وَأُسَامَةَ بْنِ زَيْدٍ قَدْ غَطَّيَا رُءُوسَهُمَا وَبَدَتْ أَقْدَامُهُمَا فَقَالَ إِنَّ هَذِهِ الأَقْدَامَ بَعْضُهَا مِنْ بَعْضٍ ‏"‏ ‏.‏ وَهَكَذَا حَدَّثَنَا سَعِيدُ بْنُ عَبْدِ الرَّحْمَنِ وَغَيْرُ وَاحِدٍ عَنْ سُفْيَانَ بْنِ عُيَيْنَةَ هَذَا الْحَدِيثَ عَنِ الزُّهْرِيِّ عَنْ عُرْوَةَ عَنْ عَائِشَةَ ‏.‏ وَهَذَا حَدِيثٌ حَسَنٌ صَحِيحٌ ‏.‏ وَقَدِ احْتَجَّ بَعْضُ أَهْلِ الْعِلْمِ بِهَذَا الْحَدِيثِ فِي إِقَامَةِ أَمْرِ الْقَافَةِ ‏.‏