al-Zuhri ابن شهاب الزهري‎, محمد بن مسلم · The Chapters on Divorce

"The Messenger of Allah (ﷺ) swore that he would not enter upon his wives for a month, and he stayed for twenty-nine days until, on the eve of the thirtieth, he entered upon me. I said: 'You swore not to enter upon us for a month.' He said: 'The month may be like this,' and he held up his (ten) fingers three times; 'or the month may be like this,' and he held up his fingers three times, keeping one…

the Prophet (ﷺ) said: "There are four kinds of women for whom there is no Li'an: a Christian woman married to a Muslim, a Jewish woman married to a Muslim, a free woman married to a slave, and a slave woman married to a free man."