U.S. Coast Guard 1989 National Boating Safety Advisory Council (NBSAC) Subcommittee on Propeller Guards report timeline chart. PDF
Houseboat Propeller Regulation Proposed and Withdrawn by USCG: Analysis by PGIC
History of Boat Propeller Safety
Mitigating Boat Propeller Injuries & Fatalities Chart
Four Volume Review of the Boating Industry’s Boat Propeller Guard Product Liability Defense