Back when I was trying to research the origin and application for a 8.25x14" (yes, that's the size) Space Saver Spare, I came across these interesting papers. I don't recall seeing these posted before. Interesting stuff.

If you click the "View" "Preview Technical Paper" on the right side of the page, you can see a preview of the first 5 pages of each paper.

"A New Spare Tire"

"The Development History of The Space Saver Spare"