YONGZHENG SIX-CHARACTER MARKS IN UNDERGLAZE BLUE WITHIN DOUBLE CIRCLES AND OF THE PERIOD (1723-1735)

A pair of bowls and covers of this pattern and of the Yongzheng period are illustrated in The Complete Collection of Treasures of the Palace Museum - 38 - Porcelains in Polychrome and Contrasting Colours, Hong Kong, 1999, no. 230. A single bowl and cover was sold at Christie's Hong Kong, 3 June 2015, lot 3147.