1. P. Weiss, J. De Physique 6 (1907) 661.
2. P. Weiss, Ann. Phys. 17(1932)97.
3. L. Neel, Ann. Phys. 18 (1932) 1.
4. For a comprehensive general view of the effective field theory see, e.g. J. S. Smart (1966) in Effective Field Theories of Magnetism, W. B. Saunders Company.
5. E. Ising, Z. Phys. 31 (1925)253.