formula reference error in GND calculation

[cheneyjin]

Hi,

I found the formula reference in GND energy calculations is difference from that in the book 'Introduction to Dislocations' by Hull & Bacon.
From the website https://mtex-toolbox.github.io/GND.html, reads:

However, in the book by Hull and Bacon:

So, the second formula should be :

$$ U_{edge}=\frac {U_{screw}}{1-\nu} $$

Cheneyjin