Prince Charles his letter to the Lady Marie his most royall sister as also another to the Prince of Orange in confirmation of the many favours passing between each other during their residence in England - Karl II. England, König 1630-1685 (Printed for William Reynor, 1642)
Reproduction of original in Thomason Collection, British Library. - The letters are dated: Royston, March 9, 1642. - Wing, C3115