The extent of his recitation in the two rak'ahs of the Zuhr prayer was the length of {Alif Lam Mim. The revelation of the Book} — Surah As-Sajdah. We estimated his standing in the last two rak'ahs to be half of that. We estimated his standing in the first two rak'ahs of the 'Asr prayer to be the extent of the last two rak'ahs of the Zuhr prayer, and we estimated his standing in the last two rak'ahs of the 'Asr prayer to be half of that (1).

130 — Chapter: The extent of recitation in the Zuhr and 'Asr prayers

805 — Musa ibn Isma'il narrated to us, Hammad narrated to us, from Simak ibn Harb, from Jabir ibn Samurah: that the Messenger of Allah — peace be upon him — used to recite in the Zuhr and 'Asr prayers "By the heaven and the Night-Comer" (At-Tariq), "By the heaven holding great stars" (Al-Buruj), and similar surahs (2).

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(1) Its chain is authentic. Hushaym — who is Ibn Bashir, and although he was a mudallis — explicitly stated that he heard it (tahdith) according to al-Nasa'i, so the suspicion of tadlis is removed. Mansur: he is Ibn al-Mu'tamir, and al-Walid ibn Muslim: he is Abu Bishr al-Basri, and Abu al-Siddiq al-Naji: he is Bakr ibn 'Amr.
It was also recorded by Muslim (452), and al-Nasa'i in "Al-Kubra" (349) via the chain of Mansur, with this isnad.
It was also recorded by al-Nasa'i in "Al-Kubra" (350) via the chain of Abu al-Mutawakkil 'Ali ibn Dawud, from Abu Sa'id, with it.
It is in "Musnad Ahmad" (10986), and "Sahih Ibn Hibban" (1828).
It was also recorded by Ibn Majah (828) via the chain of Abu Nadrah, from Abu Sa'id al-Khudri, who said: Thirty of the companions of the Messenger of Allah — peace be upon him — gathered and said: Come, let us measure the recitation of the Messenger of Allah — peace be upon him — in the prayers in which he did not recite aloud. Not two men among them differed. They measured his recitation in the first rak'ah of the Zuhr prayer as the length of thirty verses, and in the other rak'ah as half of that, and they measured that in the 'Asr prayer as half of the last two rak'ahs of the Zuhr prayer.
It is in "Musnad Ahmad" (23097). Its chain is weak.
(2) Authentic due to corroboration; it is a good chain because of Simak ibn Harb, and the rest of its narrators are trustworthy. Hammad: he is Ibn Salamah. =