Mark 12:19
"Teacher, Moses wrote for us that if someone's brother dies and he leaves behind a wife and does not leave a child, that his brother should take the wife and {father} descendants for his brother.
Genesis 38:8
Then Judah said to Onan, "Go in to the wife of your brother and perform the duty of a brother-in-law to her, and raise up offspring for your brother."
Deuteronomy 25:5-10
"When brothers dwell together and one of them dies and has no son, the wife of the deceased shall not become the wife of a {man of another family}; her brother-in-law {shall have sex with her}, and he shall take her {to himself} as wife, and he shall perform his duty as brother-in-law [with respect to] her.
Ruth 1:11-13
And Naomi said, "Return, my daughters. {Why do you still want to go with me}? [Are there] sons {in my womb} that may be husbands for you?
Ruth 4:5
And Boaz said, "On the day of your acquiring the field from the hand of Naomi, you also acquire Ruth the Moabite, the wife of the dead [man], [in order] to raise up [for] the name of the dead his inheritance."