Reference for Genesis 30:9

וַתֵּ֣רֶא לֵאָ֔ה כִּ֥י עָמְדָ֖ה מִלֶּ֑דֶת וַתִּקַּח֙ אֶת־זִלְפָּ֣ה שִׁפְחָתָ֔הּ וַתִּתֵּ֥ן אֹתָ֛הּ לְיַעֲקֹ֖ב לְאִשָּֽׁה׃

When Leah saw that she had left off bearing, she took Zilpah her handmaid, and gave her to Jacob to wife.