Anderson, K., Tharrington, J., Curtis, P., & Jones, F. (2003). Shell Characteristics of Eggs from Historic Strains of Single Comb White Leghorn Chickens and the Relationship of Egg Shape to Shell Strength. International Journal of Poultry Science, 3(1), 17–19. https://doi.org/10.3923/ijps.2004.17.19