W. M. Christie was the first to dispute this popular theory in 1925. Jack P. Lewis wrote a critique of the popular consensus in 1964. Raymond E. Brown largely supported Lewis in his review, as did Lewis' discussion of the topic in 1992's "Anchor Bible Dictionary". Sid Z. Leiman made an independent challenge for his University of Pennsylvania thesis published later as a book in 1976, in which he wrote that none of the sources used to support the theory actually mentioned books that had been withdrawn from a canon, and questioned the whole premise that the discussions were about canonicity at all, stating that they were actually dealing with other concerns entirely. Other scholars have since joined in and today the theory is largely discredited.