1. Variation and heredity of some characters in White Leghorns, Rhode Island Reds, and Barnevelders. Part 1;Axelsson;Lunds Univ. Arsskr. N. F. Aud 2 Med. Mat. Och. Naturvet,1932
2. The effect of light and specific gravity on embryo weight and embryonic mortality;Coleman;Poultry Sci.,1975
3. The porosity of the egg shell in relation to hatchability;Muller;Poultry Sci.,1940
4. Influence of the specific gravity of hen's egg on fertility, hatching power and growth of chicks;Mussehl;J. Agr. Res.,1923
5. Shell thickness in relationship to ‘shick outs' in turkey eggs;Payne;Poultry Sci.,1958