References
- HARVEY, W. R. (1960) United States Department of Agriculture, ARS-20-8, 157pp
- WORKING GROUP 3 (1981) World's Poultry Science Journal 37: 218–221
- WORKING GROUP 3 (1984) World's Poultry Science Journal 40: 86–87
- WORKING GROUP 3 (1986) World's Poultry Science Journal 42: 276–284
- WORKING GROUP 3 (1989) World's Poultry Science Journal 45: 189–192
- WORKING GROUP 3 (1992) World's Poultry Science Journal 48: 269–270
- WORKING GROUP 3 (1994) World's Poultry Science Journal 50: 187–189
- WORKING GROUP 3 (1996) World's Poultry Science Journal 52: 81–83