Letter to Shelley, August 1820, in H. E. Rollins (ed.) 'The Letters of John Keats' (1958) vol. 2, p. 323; echoing Edmund Spenser 'The Faerie Queen' (1596) bk. 2, canto 7, st. 28, l. 5: 'And with rich metal loaded every rift'
William Carlos Williams, A. Walton Litz, Christopher MacGowan (1991). “The Collected Poems of William Carlos Williams: 1939-1962”, p.54, New Directions Publishing