SV waves

Similarly.

$$\begin{eqnarray} W_{44} = W_{11} - \frac {(W_{13} + W_{44})^2}{W_{33} - W_{44}}\end{eqnarray}$$ (25)

which is to say

(<I>W₁₃I> + <I>W₄₄I>)² = (<I>W₁₁I> - <I>W₄₄I>)(<I>W₃₃I> - <I>W₄₄I>) (26)

and for SH waves

<I>W₄₄I> = <I>W₆₆I> (27)

which is an exact result