Human Body Detection, a bibliography by Bram van der Vlist in 2005. He was a student Department of Industrial Design Technical University Eindhoven (The Netherlands) working on propeller safety devices.
Houseboat Propeller Regulation Proposed and Withdrawn by USCG: Analysis by PGIC
History of Boat Propeller Safety
Mitigating Boat Propeller Injuries & Fatalities Chart
Approaches to Prevent Outboard Motors From Flipping Into Boats After Striking Floating or Submerged Objects
Why Outboards Used in Bass Tournaments Disproportionately Break Off & Flip into Boats Compared to Other Outboard Motors
Four Volume Review of the Boating Industry’s Boat Propeller Guard Product Liability Defense