(51) باب الْقَدْرِ الَّذِي يُحَرِّمُ مِنَ الرَّضَاعَةِ .
It was narrated from 'Abdullah bin Az-Zubair that the Prophet said:
"Suckling once or twice does not make (marriage) prohibited."
Reference: Sunan an-Nasa'i 3309
In-book reference: Book 26, Hadith 114
English translation: Vol. 4, Book 26, Hadith 3311