My Guide to the Doctors
My Guide to the Doctors was a document written by River Song during her afterlife in the Library. It contained information on every incarnation of the Doctor that River had encountered during her life.
An excerpt from the document was tracked down by Yasmin Khan for the Thirteenth Doctor to compile in a book that she had written. The excerpt consisted of an introduction by the author and a collection of paragraphs summing up the Doctor's incarnations, beginning from the First Doctor, and cutting off as the Thirteenth Doctor's paragraph begins: "Well, I don't think anyone saw this coming! The Doctor finally-". (PROSE: A Short History of Everyone)