A short excerpt in English may be found in Allan Gilbert's Machiavelli Volume One.
In 1503, one year after his missions to Cesare Borgia, Machiavelli wrote a short work, Del modo di trattare i sudditi della Val di Chiana ribellati (On the Way to Deal with the Rebel Subjects of the Valdichiana).
Machiavelli declares that when dealing with rebellious peoples, such as in Valdichiana, the ruler must either placate them or eliminate them.
[2] Machiavelli also witnessed the bloody vengeance taken by Borgia on his mutinous captains at the town of Sinigaglia (December 31, 1502), later writing a famous account.
[3] In much of his early writings, Machiavelli argues that “one should not offend a prince and later put faith in him.”