拍品專文
This drawing is page no. 81 from the Red Notebook, 1969-1977, previously known as 'Notebook 3'. This notebook was 'begun in 1969 ... and continued intermittently from the front and back until 1974, with some pages being redrawn on one or more occasion up to 1977' (see Red Notebook 1969-1977', 4, op. cit, p. 193).