Contribution to Associative Laws in Subtractive Group

The concept of a subtractive group was first introduced by M.A. Kazim and F. Husain [1]. The authors, therein, have defined a subtractive group G with a two-sided binary operation '-'called 'Subtraction' under the following postulates :

I (i) Right Difference : xy ∈ G.

for any       x, y ∈ G.

(ii) Left Difference : yx ∈ G.