[Abu 'Eisa said:] This Hadith is Hasan Sahih.
In-book : Book 21, Hadith 31
English translation : Vol. 3, Book 19, Hadith 1570
21. The Book on Military Expeditions
باب مَا جَاءَ إِذَا اسْتَيْقَظَ أَحَدُكُمْ مِنْ مَنَامِهِ فَلاَ يَغْمِسْ يَدَهُ فِي الإِنَاءِ حَتَّى يَغْسِلَهَا