Hadith 17:586
'Isa ibn Yunus narrated to us, from al-Awza'i, who said: 'Umar ibn 'Abd al-'Aziz used to write to him, and he would begin with him, and he did not see any harm in that.
حدثنا عيسى بن يونس عن الأوزاعي قال كان عمر بن عبد العزيز يكتب إليه فبدأ به فلم ير به بأسا