He said: There are narrations on this topic from Abu Bakrah, Ayman bin Khuraim, and Ibn 'Umar
Abu 'Eisa said: The Hadith of Anas is a Hasan Sahih Gharib Hadith.
In-book : Book 14, Hadith 4
English translation : Vol. 1, Book 12, Hadith 1207
14. The Book on Business
باب مَا جَاءَ أَنَّ مِفْتَاحَ الصَّلاَةِ الطُّهُورُ