Sunan an-Nasa'i 634
سنن النسائي#634SahihIt was narrated that Malik bin Al-Huwairith said:"I came to the Prophet (S.A.W) with a cousin of mine" - on an another occasion he said: "with a companion of mine" - "and he said: 'When the two of you travel, call the Adhan and the Iqamah, and let the older of you lead the prayer
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Abu GhuddahSahih
Al-AlbaniSahih
Zubair Ali ZaiSahih - Agreed Upon
In-book reference: 7:9