Musannaf Ibn Abi Shaybah

Hazrat Imran bin Muslim narrates that Hazrat Suwaid said: If I had the strength to both give the adhan and lead the prayer, I would have done so. Hazrat Imran says that I mentioned this to Hazrat Mus'ab bin Sa'd, and he said: It is not Sunnah for one person to both give the adhan and lead the prayer.

Hazrat Asbagh narrates that Hazrat Ibn Umar (may Allah be pleased with them) used to give the call to prayer (adhan) and also lead the prayer (imamat) while traveling.

Hazrat Umar says that if it were not Sunnah for the call to prayer (adhan) and leading the prayer (imamat) to be performed by separate individuals, I would have given the adhan as well.