(19) باب جَوَازِ جِمَاعِهِ امْرَأَتَهُ فِي قُبُلِهَا مِنْ قُدَّامِهَا وَمِنْ وَرَائِهَا مِنْ غَيْرِ تَعَرُّضٍ لِلدُّبُرِ
Jabir (b. Abdullah) (Allah be pleased with him) reported that the Jews used to say that when one comes to one's wife through the vagina, but being on her back, and she becomes pregnant, the child has a squint. So the verse came down:
" Your wives are your ti'Ith; go then unto your tilth, as you may desire."
Reference: Sahih Muslim 1435 b
In-book reference: Book 16, Hadith 139
USC-MSA web (English) reference(deprecated numbering scheme): Book 8, Hadith 3364