كتاب النكاح
13  
Marriage
(5a)
Chapter: Sexual Intercourse - Section 1
(5)
باب المباشرة - الفصل الأول
Mishkat al-Masabih 3184
He said that in the period when the Qur'an was coming down they used to withdraw the penis.* * i.e. before emission of semen, to avoid conception. (Bukhari and Muslim.) Muslim added that the Prophet heard of that and did not prohibit it.
وَعنهُ كُنَّا نَعْزِلُ وَالْقُرْآنُ يَنْزِلُ. مُتَّفَقٌ عَلَيْهِ. وَزَادَ مُسْلِمٌ: فَبَلَغَ ذَلِكَ النَّبِيَّ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَلم ينهنا
  مُتَّفق عَلَيْهِ   (الألباني) حكم   :
Reference : Mishkat al-Masabih 3184
In-book reference : Book 13, Hadith 102