Roberty provided no evidence to suggest that the Vatican does, in fact, possess any additional copy. While the contents of one part of the Vatican library have been catalogued and have long been available to researchers and scholars, the remainder of the library is without a public catalogue, and though researchers may view any work within, they must first name the text they require, a serious problem for those who do not know what is contained by the library. The Pope responded on April 13, 2006: