Combinations	Coupling
$[{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{i} \oplus {(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{j}]$	coupling of I˚ degree
${{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{i} \oplus [{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{j} \oplus {(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{k}]}$	coupling of II˚ degree
$[{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{i} \oplus {(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{j}] \oplus [{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{k} \oplus {(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{r}]$	coupling of III˚ degree
${{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{i} \oplus [{(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{j} \oplus {(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{k} \oplus {(π_{1}^{\pm} \otimes π_{2}^{\pm})}_{r}]}$	coupling of IV˚ degree