Sir John Gardner Wilkinson (1828). Materia hieroglyphica. Malta: privately printed. hlm. 22. Diakses tanggal 26 July 2016.
Alfred Lucas, John Richard Harris (2011). Ancient Egyptian Materials and Industries (Edisi reprint of 4th edition (1962), revised from first (1926)). Mineola, NY: Dover Publications. hlm. 60. ISBN9780486404462. Diakses tanggal 26 July 2016.