Mike Bromfield, Guy Gratton & Mark Young, The Effects of Stick Force Gradient on Pilot Mental Demand, AIAA Atmospheric Flight Mechanics Conference, AIAA SciTech, (AIAA 2015-0751 Jan 2015 Kissimmee FL, USA).
http://dx.doi.org/10.2514/6.2015-0751
MA Bromfield & GB Gratton, Testing the relationship between stick force gradient, workload, and loss of control in light aeroplanes, SETP Cockpit Jul-Dec 2012, pp6-32.
MA Bromfield & GB Gratton, Factors affecting the apparent longitudinal stick-free static stability of a typical high-wing light aeroplane, RAeS Aeronautical Journal, vol 116 No.1179, pp467-600 (May 2012)
M Bromfield & GB Gratton, Supporting the investigation of factors affecting loss of control of light aircraft, Proceedings of the 40th Annual International Symposium - Society of Flight Test Engineers, Linkoping, Sweden, Sept 2009
M Bromfield & GB Gratton, Factors affecting loss of control in general aviation aircraft, Proceedings of the 39th Symposium of the Society of Experimental Test Pilots, San Diego, California, USA (March 2009)
Brunel University Research Archive: Factors affecting loss of control in general aviation aircraft
Michael Bromfield - PhD Thesis
J Brownlow, N Everett, G Gratton, M Jackson, I Lee, J Thorpe, A study of fatal stall or spin accidents to UK registered light aeroplanes 1980 to 2008, General Aviation Safety Council 2010.
If you want to track them down, Mike Bromfield is at Coventry University, Guy Gratton sits between Brunel and Cranfield Universities and the National Centre for Atmospheric Science - both have webpages that makes them easy enough to contact. I think that the GASCo report you can get from them directly.
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