It is permissible for a man to have intercourse with his wife from the front or from the back, without entering the behind Sahih Muslim 1435 a
Translation
Jabir (Allah be pleased with him) declared that the Jews used to say
When a man has intercourse with his wife through the vagina but being on her back. the child will have squint, so the verse came down:" Your wives are your tilth; go then unto your tilth as you may desire" (ii. 223)