Nope, not that one...
It's most certainly not that one - it was either an entire booklet, or a section, dedicated entirely to the Soryus/Unryus. As indicated, I'm not even entirely sure it was even a Gakken at all. (Though there were many, and it well could have been.)
But thanks for posting that cool cover-pic! (Note Kaga, in the background as well.)