Muwatta Malik· موطأ مالك
Muwatta Malik 405
When a sick man is unable to prostrate he should motion with his head, and…
মুয়াত্তা ইমাম মালিক ৪০৫ · মুয়াত্তা মালিক•Shortening the Prayer
وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ نَافِعٍ، أَنَّ عَبْدَ اللَّهِ بْنَ عُمَرَ، كَانَ يَقُولُ إِذَا لَمْ يَسْتَطِعِ الْمَرِيضُ السُّجُودَ أَوْمَأَ بِرَأْسِهِ إِيمَاءً وَلَمْ يَرْفَعْ إِلَى جَبْهَتِهِ شَيْئًا .
Narrator: Yahya
Yahya related to me from Malik from Nafi that Abdullah ibn Umar used to say, "When a sick man is unable to prostrate he should motion with his head, and not raise anything to his forehead- Salim al-HilaliMauquf Sahih