[Footnote 16: The ambassador of Otho was provoked by the
Greek excuses, cum Christophori filiam Petrus Bulgarorum
Vasileus conjugem duceret, Symphona, id est consonantia
scripto juramento firmata sunt, ut omnium gentium Apostolis,
id est nunciis, penes nos Bulgarorum Apostoli praeponantur,
honorentur, diligantur, (Liutprand in Legatione, p. 482.)
See the Ceremoniale of Constantine Porphyrogenitus, tom. i.
p. 82, tom. ii. p. 429, 430, 434, 435, 443, 444, 446, 447,
with the annotations of Reiske.]