1. Dudley, N.A.: ‘Output Pattern in Repetitive Tasks’, May, 1955, Ph.D. Thesis, University of Birmingham
2. Belbin, R.M.: Compensating Rest Allowances: Some Findings and Implications for Management Arising from Recent Research, (College of Aeronautics 1956 October), p. 9 Note No. 54
3. ‘Accuracy of Rating in Time Study’, A Research Report based upon an investigation of time study rating practice, carried out in the U.K. during 1950 – 1951, The Work Measurement Research Unit, University of Birmingham, Department of Engineering Production, March, 1952 (limited edition)