L. von Pastor: Geschichte der Päpste seit dem Ausgang des
Mittelalters
. Band VI. 1913; VII. 1920. (Of these volumes of the
German, covering the years 1550-65, there is as yet no English
translation).

P. Herre: Papsttum und Papstwahl im Zeitalter Philipps, II. 1907.

J. McCabe: Crises in the History of the Papacy. 1916. (Popular).

Mandel Creighton: op. cit.

L. von Ranke: History of the popes, their church and state, in the
sixteenth and seventeenth centuries
, translated from the German by
Sarah Austin. Vol. 1, 1841. (Translation of Ranke's Die römischen
Päpste
, of which the first edition appeared 1834-6. A classic).

H. M. Vaughan: The Medici Popes. 1908. (Popular, sympathetic).

G. Droysen: Geschichte der Gegenreformation. 1893. (Oncken's
Series).

E. Rodocanachi: "La Réformation en Italic," Revue des Deux Mondes,
March, 1915.

Lord Acton: Lectures on Modern History, 1906, pp. 108 ff.

J. A. Symonds: The Catholic Reaction. 2 vols. 1887.