A chart showing how the sounds of the word 'elf' have changed in the history of English. The chart cites Richard M. Hogg, "A Grammar of Old English", Volume 1: Phonology (Oxford: Blackwell, 1992). It has also been published in Alaric Hall, "Elves in Anglo-Saxon England: Matters of Belief, Health, Gender and Identity", Anglo-Saxon Studies, 8 (Woodbridge: Boydell, 2007), p. 178 (fig. 7).