John Ruskin (1800). “The Seven Lamps of Architecture: Also, Lectures on Architecture and Painting; The Study of Architecture; Sesame and Lilies; Unto this Last; The Queen of the Air; The Storm-cloud of the Nineteenth Century”
John Ruskin, Louisa Caroline Tuthill (1872). “The True and the Beautiful in Nature, Art, Morals, and Religion, Selected from the Works of John Ruskin”, p.408
John Ruskin (1854). “On the nature of Gothic architecture: and herein of the true functions of the workman in art. Being the greater part of the 6th chapter of the 2nd vol. of 'Stones of Venice'. [48 p.].”, p.19
John Ruskin, Louisa Caroline Tuthill (1860). “The True and the Beautiful in Nature, Art, Morals and Religion: Selected from the Works of John Ruskin...”, p.422