Mark Rothko (1903-1970), Untitled, signed and dated ‘MARK ROTHKO 1955’ (on the reverse), oil on canvas, 69¼ x 61¾in. (175.8 x 157cm.). Painted in 1955. Christie’s Images Ltd 2012.
(via Rothko & The Abstractionists: First major canvas by Rothko at a London auction in a decade)