A brief allusion to my sources of information will not seem superfluous:
I have carefully studied all the leading contemporary chronicles and
pamphlets of Holland, Flanders, Spain, France, Germany, and England; but,
as the authorities are always indicated in the notes, it is unnecessary
to give a list of them here. But by far my most valuable materials are
entirely unpublished ones.

The archives of England are especially rich for the history of the
sixteenth century; and it will be seen, in the course of the narrative,
how largely I have drawn from those mines of historical wealth, the State
Paper Office and the MS. department of the British Museum. Although both
these great national depositories are in admirable order, it is to be
regretted that they are not all embraced in one collection, as much
trouble might then be spared to the historical student, who is now
obliged to pass frequently from the one place to the other, in order to,
find different portions of the same correspondence.

From the royal archives of Holland I have obtained many most important,
entirely unpublished documents, by the aid of which I have endeavoured to
verify, to illustrate, or sometimes to correct, the recitals of the elder
national chroniclers; and I have derived the greatest profit from the
invaluable series of Archives and Correspondence of the Orange-Nassau
Family, given to the world by M. Groen van Prinsterer. I desire to renew
to that distinguished gentleman, and to that eminent scholar M. Bakhuyzen
van den Brink, the expression of my gratitude for their constant kindness
and advice during my residence at the Hague. Nothing can exceed the
courtesy which has been extended to me in Holland, and I am deeply
grateful for the indulgence with which my efforts to illustrate the
history of the country have been received where that history is best