Matings: The bounty of the world is from the mating of the Small Face [Zair Anpin] with the Female. These are five matings — Israel and Rachel, Jacob and Rachel, Israel and Leah, Jacob and Leah from the chest and above, and Jacob and Leah from the chest and below.
Leah — Jacob and the Patriarchs
Asarah Perakim LeRamchal 6:1