Dear Richard,
This is a complex subject which has never been fully covered in any single book to my knowledge. A totally neglected, in my view, component was the global I.G. Farben chemical cartel. The world's largest chemical company at the time. Germany had coal and could turn it into gasoline, aviation fuel and lubricants. The link between Standard Oil and I.G. Farben is only partially known but there was a relationship between the two that lasted throughout the war.
I offer the following information reluctantly but I trust the footnotes will be helpful to you and other researchers.
http://en.wikipedia.org/wiki/Oil_Cam...f_World_War_II
The following was published on July 29, 1945 in Sunday morning newspapers in the US after clearance by the Office of War Information.
"Improved techniques for the production of synthetic petroleum products.
"Hydrogenation plants operating at extremely high pressures.
"New catalysts permitting the Germans to convert oil to high octane gasoline more quickly than was known here.
"Details on German refinements in the gas synthesis method of producing liquid fuels and lubricants from coal."
Best,
Ed