What is the ruling on the paternity of a child born to a wife that demonstrably could not have been conceived by the husband during the marriage?

Primary text

The lineage of a child born to a wife, where it is known that the child could not have been conceived by the husband during the marriage, is not attributed to him, and no denial of paternity (Nafy) is required. This applies, for instance, if the child is born less than six months after the marriage. This is the position of all scholars whose views are known, as it is established that conception occurred before the marriage.