The Nuttall Encyclopedia
Name given to a union of several States in defence or promotion of the common good, while each State is independent of the rest in local matters.
Wood, James, ed. Entry for 'Union, Federal'. The Nuttall Encyclopedia. https://www.studylight.org/encyclopedias/eng/nut/u/union-federal.html. Frederick Warne & Co Ltd. London. 1900.