Alqama and Aswad reported,

The two of them entered upon Abdullah bin Masud, and he asked, "Have those behind you prayed?"They replied, "Yes."So he stood between them, placing one on his right and the other on his left, then we bowed and placed our hands on our knees. He struck our hands, then joined his palms together and placed them between his thighs. When he had finished praying, he said, "This is how the Messenger of Allah ﷺ did it."

Azami 2303

Sahih

عن علقمة والأسود

أنهما دخلا على عبد الله بن مسعود فقال: أصلى من خلفكم؟ قالا: نعم. فقام بينهما وجعل أحدهما عن يمينه، والآخر عن شماله، ثم ركعنا. فوضعنا أيدينا على ركبنا فضرب أيدينا. ثم طبق بين يديه، ثم جعلهما بين فخذيه، فلما صلى قال: هكذا فعل رسول الله ﷺ.

الأعظمي 2303صحيح
Contents
Reference
Commentary
Ayat
Collection
Jami al-Kamil
Book
Prayer
Chapter
Leadership
Section
Position of the imam with two people
Numbering
Jami al-Kamil 2303 (2nd edition)
Azami 2303