
Source: Practical Pictorial Photography, 1898, Composition and clouds considered as an aid to expression, p. 105
Quote of Vincent van Gogh, from his 'First Sunday Sermon' http://www.vggallery.com/misc/archives/sermon.htm: 'I Am a Stranger on the Earth..'; 29 October 1876
1870s
Source: Practical Pictorial Photography, 1898, Composition and clouds considered as an aid to expression, p. 105
Quote from Friedrich's Diary-note, 1803; as cited by C. D. Eberlein in C. D. Friedrich - Bekenntnisse, pp. 72-73; translated and quoted by Linda Siegel in Caspar David Friedrich and the Age of German Romanticism, Boston Branden Press Publishers, 1978, p. 45
1794 - 1840
Source: 1961 - 1975, Barbara Hepworth, A Pictorial autobiography', 1970, p. 280
1970s - 1980s, interview with Deborah Salomon in 'New York Times', 1989
Source: 2000 - 2011, Cy Twombly, 2000', by David Sylvester (June 2000), p. 173
Diary-note of Boudin, 3 December, 1856; as cited in the description of his painting 'Sky, Setting Sun, Bushes in Foreground' http://www.muma-lehavre.fr/en/collections/artworks-in-context/eugene-boudin/boudin-skies, by the Muma-museum, Le Havre
A quote from Boudin's personal diary sheds remarkable light on a small group of his sky studies
1850s - 1870s