^Nutt, The Celtic Doctrine of Re-Birth (1897), p. 149.
^"Celtic Gods, Crom Cruaich". Magic of Mythology. Retrieved 9 December 2010. Festivals: Domhnach Crom Dubh - Last Sunday in July or First Sunday in August. During Lughnasadh - (The August festival of Lugh)
^as in the Scottish Gaelic saying DiDòmhnaich Crum Dubh, plaoisgidh mi an t-ugh. "Crooked black Sunday, I’ll shell the egg."