The above mentioned tradition has also been transmitted by Mamar through a different chain of narrators to the same effect.
Explanation & Benefits
Shaykh Umar Farooq Saeedi
895. Commentary:
It is preferable and superior that a person's forehead be uncovered in prostration (sujud) and touch the ground or prayer mat directly. It is not established that the Prophet Muhammad (sallallahu alayhi wa sallam) performed prostration on the edge or fold of his turban, although some reports from the Companions (radi Allahu anhum ajma'in) are indeed established. See: [نيل الاوطار 290/2]
Furthermore, along with the forehead, the nose should also touch the ground.
Source: Sunan Abu Dawood – Commentary by Shaykh Umar Farooq Saeedi, Page: 895