For a Qianlong vase with a Ru-type glaze in the National Palace Museum, Taipei, see the Museum's exhibition Qingdai danseyou ciqi /Special Exhibition of Ch'ing Dynasty Monochrome Porcelains in the National Palace Museum, Taipei, 1989, cat. no. 88, and for another sold in our Hong Kong rooms, 5^th October 2011, lot 1934. Another Qianlong vase with a Guan-type glaze, in the Walters Art Gallery, Baltimore, is published in S.W. Bushell, Oriental Ceramic Art, London, 1981 (1896), col. pl. LXXVII. For a teadust glazed 'three ram' vase of Qianlong mark and period see one from the collections of T.Y. Chao and Ira and Nancy Koger, sold three times in these rooms, 1979, 1986 and 1992, and once in our New York rooms, 1990, illustrated in Sotheby's. Thirty Years in Hong Kong, Hong Kong, 2003, pl. 157; and a rare celadon-glazed version sold twice in these rooms 8^th October 2006, lot 1014, and again, 8^th October 2009, lot 1632.