University Of Oxford First World War Poetry Digital Archive
Dataset published 2011 via Bodleian Libraries, University of Oxford
Revision of lines 9-11. Drafted on 23 March 1917 in France; a fair copy was included in a letter to Colin Owen on 24 March 1917. Revised at Craiglockhart in August-September 1917. This is no. 91 in ed. 'The Complete Poems and Fragments'.