Sunan Abi Dawud, Hadith 3210 ⓘ
The tradition mentioned above has also been transmitted by Humaid b. Hilal with a different chain of transmitters and to the same effect. This version adds: "And deepen (the graves)."
حَدَّثَنَا أَبُو صَالِحٍ، - يَعْنِي الأَنْطَاكِيَّ - أَخْبَرَنَا أَبُو إِسْحَاقَ، - يَعْنِي الْفَزَارِيَّ - عَنِ الثَّوْرِيِّ، عَنْ أَيُّوبَ، عَنْ حُمَيْدِ بْنِ هِلاَلٍ، بِإِسْنَادِهِ وَمَعْنَاهُ زَادَ فِيهِ " وَأَعْمِقُوا " .
also referenced under: Hadith 3216 (DarusSalam)