Borghouts, J. F. (2010), Egyptian: an introduction to the writing and language of the Middle Kingdom, 2 vols. Egyptologische Uitgaven 24, page 74, note 1
Gardiner, Alan Henderson (1957), Egyptian grammar being an introduction to the study of hieroglyphs, 3rd, revised edition, page 475
Miniaci, Gianluca and Cornelius von Pilgrim (2022), An unusual mutilation of the crocodile hieroglyphic sign in an early Middle Kingdom stela from the Sanctuary II of Heqaib at Elephantine. In Miniaci, Gianluca and Wolfram Grajetzki (eds), The world of Middle Kingdom Egypt (2000-1550 BC): Contributions on archaeology, art, religion, and written sources. Volume III, 259-272, comment on the mutilation of the sign