The Nuttall Encyclopedia
A Church council attended by 764 ecclesiastics under the auspices of Pius IX., which assembled on December 8,1869, and by a majority of nearly 481 decreed the doctrine of Papal Infallibility.
Wood, James, ed. Entry for 'Vatican Council'. The Nuttall Encyclopedia. https://www.studylight.org/encyclopedias/eng/nut/v/vatican-council.html. Frederick Warne & Co Ltd. London. 1900.