Sayyiduna Abu Hurayrah (may Allah be pleased with him) came until he stayed with Abu Kulthum al-Dawsi, and they discussed the middle prayer (al-salat al-wusta) among themselves. He said: We too differed about it just as you differ, while we were in the courtyard of the house of the Messenger of Allah (peace and blessings be upon him), and among us was the righteous man Abu Hashim bin Utbah bin Rabi'ah bin Abd Shams (may Allah be pleased with him), and he said: I will find out about it for you. So he went to the Messenger of Allah (peace and blessings be upon him), and he was at ease with him (peace and blessings be upon him); he asked permission, entered upon him (peace and blessings be upon him), then came out to us and informed us that it was the Asr prayer.
Hadith Referenceالمعجم الكبير للطبراني / باب الشين / 7167