Abu Dawud Book 2, Hadith Number 613.
Chapter : Not known.
Narated By Abdullah ibn Mas’ud : Alqamah and al-Aswad sought permission from Abdullah (ibn Mas’ud) for admission, and we remained sitting at his door for a long time. A slave-girl came out and gave them permission (to enter). He (Ibn Mas’ud) then got up and prayed (standing) between me (al-Aswad) and him (Alqamah). He then said: I witnessed the Apostle of Allah (PBUH) doing similarly.