Abarca B. LD, Quintana L JA, Casaubon H. MT, Rosales SG. Assessment of Eggshell Quality Before and After Incubation from 29 and 46 Weeks-old Leghorn Hens. Int. J. Poult. Sci. 2011;10(12):977–982. doi:10.3923/ijps.2011.977.982