Aerodynamic characteristics in the approach, superfine and negative pitch ranges of two four-bladed propellers with N.A.C.A. series 16 blade sections : report of tests carried out jointly by the technical staffs of de Havilland Propellers, Limited, and Rotol, Limited.
Aeronautical Research Council,issuing body.
Great Britain.Her Majesty's Stationery Office.
April, 1957.