Giovanni Amelino-Camelia, "Doubly-Special Relativity: First Results and Key Open Problems." Int. J. Mod. Phys. D11 (2002) 1643. Online copy at http://arxiv.org/abs/gr-qc/0210063
... Axioms
a+0 = a
a+(b+) = (a+b)+
The first is referred as AP1, the second as AP2.
The Properties
Uniqueness: (a+b) is unique. i.e. If (a.b) also satisfies ...