The above excerpt is from an essay on long poems by Peter Middleton. Read the whole essay here: http://jacketmagazine.com/40/middleton-long-poem.shtml#fn13
Bunting's poems is in this collection of his: Basil Bunting, ‘On the Fly-leaf of Pound’s Cantos,’ Collected Poems (London: Fulcrum Press, 1970), 122.