My own book Nation & Race gets into skull shape in detail. I explore Mediterranean race theory vs. Nordic race theory as well. Incidentally, Sergi proved that the Germans were also predominantly brachycephalic, not dolichocephals like the true Nordics. Basically a lot of Nazi race theory was rooted in mythology (e.g., the “Aryan race”).
Thank you to the person who sent this along. Much appreciated since it (in part) supports my own thesis.