Baronius (Annal. Eccles. A.D. 874, No. 2) has drawn this story from a MS. of Erchempert, who died at Capua only fifteen years after the event. But the cardinal was deceived by a false title, and we can only quote the anonymous Chronicle of Salerno (Paralipomena, c. 110), composed towards the end of the 10th century, and published in the second volume of Muratori's Collection. See the Dissertations of Camillo Pellegrino, tom. ii. pars i. p. 231 - 281, etc.