In bibliology, the documentary hypothesis (DH) is one of the models used by biblical scholars to explain the origins and composition of the Torah, the first five books of the Hebrew Bible (Tanakh): Genesis, Exodus, Leviticus, Numbers, and Deuteronomy. A version of the documentary hypothesis, frequently identified with the German scholar Julius Wellhausen, was almost universally accepted for most of the 20th century. The DH posited that the Torah is a compilation of four originally independent documents: the Jahwist, Elohist, Deuteronomist, and Priestly sources, frequently referred to by their initials. The first of these, J, was dated to the Solomonic period. E was dated somewhat later, in the 9th century BCE, and D was dated just before the reign of King Josiah, in the 7th or 8th century BCE. Finally, P was generally dated to the time of Ezra in the 5th century BCE. The sources would have been joined at various points in time by a series of editors or "redactors".