Ibn Ezra on Leviticus 10:10/אבן עזרא על ויקרא י׳:י׳

1AND BETWEEN THE UNCLEAN AND THE CLEAN. Among cattle and things that swarm in the water and that fly. Therefore the section opening with the words These are the living things (Lev. 10:11), and then the sections dealing with the woman who gives birth (Lev. 12:1-8) and the leprosy that is found in humans (Lev. 13:1-46), on garments (Lev. 13:47-59) and in houses (Lev. 14:33-53); one who experiences a seminal emission (Lev. 15:16-18); a male or female who experiences a flux (Lev. 15:1-15, 25-33); and a menstruant (Lev. 15:19-24) follow this section. This is the meaning of and between the unclean and the clean.