Block, P. (2001). Flawless Consulting. Jossey-Bass/Pfeiffer Search in Google Scholar
Cockman, P. Evans, B. and Reynolds, P., (1996). Client-Centred Consulting. McGraw- Hill Search in Google Scholar
Rackham, N. (1995). SPIN Selling. Routledge Search in Google Scholar
Office for National Statistics ‘Trends in Self Employment in the UK’ 7 February 2018 Search in Google Scholar
Office for National Statistics ‘Self-employed workers in the UK 2014’, 20 August 2014 Search in Google Scholar