lower center in plate: Oliverus Cromwell; lower left in plate: R. Walker pinx.; by later hand, lower center in ink: mortus 1658; lower right in plate: P. Pelham fecit et excudt. 1723
- Smith, John Chaloner. British mezzotinto portraits, being a descriptive catalogue of these engravings from the introduction of the art to the early part of the present century. 4 vols. London: Henry Sotheran and Co., 1884.