Read the link attached to my original post- or any other book on the battle.
Notice how its called " Zhukov's offensive" " Zhukovs plan." Shtern was the general commander of the area but Zhukov was the commander of the army that faced the Japanese. Also its worth noting that that all the other commanders referred to Zhukov for orders and that Zhukov didn't take orders from Shtern, only directly from the Kremlin. Make no mistake- Zhukov was in charge.
As a general rule of thumb, it's best not to cite wikipedia, anyone could have written it.