NASAI-KUBRA 495:
from Kaʿb b. ʿUjrah —
The prayer when travelling is two rakʿahs, the prayer of [Eid] ul-Adha is two rakʿahs, the prayer of [Eid] ul-Fitr is two rakʿahs and the prayer of Jumuʿah is two rakʿahs, complete not shortened, as stated by Muhammad ﷺ, Sufyan said: On one occasion Zubaid said: I think he was narrating it from ʼUmar. ‘Abdur-Rahman said: Without a doubt. Yazeed - i.e., bin Haroon bin Abi Laila - said: l heard ʿUmar. (Using translation from Aḥmad 257)
الكبرى للنسائي ٤٩٥:
عن كعب بن عجره —
قَالَ عُمَرُ «صَلَاةُ الْأَضْحَى رَكْعَتَانِ وَصَلَاةُ الْفِطْرِ رَكْعَتَانِ وَصَلَاةُ الْجُمُعَةِ رَكْعَتَانِ وَصَلَاةُ الْمُسَافِرِ رَكْعَتَانِ تَمَامٌ غَيْرُ قَصْرٍ عَلَى لِسَانِ نَبِيَّكُمْ ﷺ وَقَدْ خَابَ مَنِ افْتَرَى»
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