Yahya related to me from Malik from Ibn Shihab from Salim ibn Abdullah from his father that Umar ibn al-Khattab, when he went to Makka, used to lead them in prayer and do two rakas and then say, "People of Makka,complete the prayer, we are a group travelling."  

أَنَّ عُمَرَ بْنَ الْخَطَّابِ كَانَ إِذَا قَدِمَ مَكَّةَ صَلَّى بِهِمْ رَكْعَتَيْنِ ثُمَّ يَقُولُ يَا أَهْلَ مَكَّةَ أَتِمُّوا صَلاَتَكُمْ فَإِنَّا قَوْمٌ سَفْرٌ  

Yahya related the same as that to me from Malik from Zayd ibn Aslam from his father from Umar ibn al-Khattab.  

عَنْ عُمَرَ بْنِ الْخَطَّابِ مِثْلَ ذَلِكَ  

Yahya related to me from Malik from Nafi that Abdullah ibn Umar used to pray four rakas behind the imam at Mina, and when he prayed by himself he would pray two rakas.  

أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ كَانَ يُصَلِّي وَرَاءَ الإِمَامِ بِمِنًى أَرْبَعًا فَإِذَا صَلَّى لِنَفْسِهِ صَلَّى رَكْعَتَيْنِ  

Yahya related to me from Malik from Ibn Shihab that Safwan said, "Abdullah ibn Umar used to come and visit Abdullah ibn Safwan and he would pray two rakas with us, and when he went away we would stand and complete the prayer."  

أَنَّهُ قَالَ جَاءَ عَبْدُ اللَّهِ بْنُ عُمَرَ يَعُودُ عَبْدَ اللَّهِ بْنَ صَفْوَانَ فَصَلَّى لَنَا رَكْعَتَيْنِ ثُمَّ انْصَرَفَ فَقُمْنَا فَأَتْمَمْنَا