John Ruskin (1875). “Proserpina: Studies of Wayside Flowers, While the Air was Yet Pure Among the Alps, and in the Scotland and England which My Father Knew”, p.186
John Ruskin (1868). “Time and Tide, by Weare and Tyne. Twenty-five letters to a Working Man of Sunderland (Thomas Dixon) on the laws of work ... Second edition”, p.37