Across, R. (2005). Psychology, the science and mind and behaviour. London: Dubai for Hodder Arnold Euston.
 Afful-Broni, A. (2004). Theory and practice of educational leadership in Ghana. Accra: Yamens Press Ltd.
 Agarwal, A. (2008). Employee motivation. URL (last checked 25 November 2009). http://ezinearticles.com
 Alderfer, C. (1972). Existence, relatedness & growth. New York: Free Press.
 Baumeister, R. F., & Voh, K. D. (2004). Handbook of self-regulation: Research, theory and applications. New York: Guilford Press.
 Blanchard, S., & Witts, D. (2009). Best practices in employee motivation. URL (last checked 29 December 2009). http://www.buzzle.com
 Boldman, L. G., & Deal, T. E. (2003). Reframing organisation: Artistry, choice and leadership (3rd ed.). San Francisco, CA: Jossey-Bass Press.
 Buchanan, K. (2006). Job performance and satisfaction. URL (last checked 24 October 2009). http://ezinearticles.com
 Campbell, S. P., & Campbell, R. S. (1988). Productivity in organizations: New perspectives from inductrial and organizational psychology. San Francisco, CA: Jossey-Bass.
 Cory, C. (2006). Equity theory and employee motivation. URL (last checked 27 November 2009). http://www.buzzle.com
 Davidoff, L. L. (1987). Introduction to psychology (3rd ed.). New York: McGraw-Hill.
 Easterby-Smith, M., Thorpe, R., & Lowe, A. (2002). Management research: An introduction. London: Sage Publications.
 Fairweather, A. (2005). 3 steps to stop absence and make people happy at work. URL (last checked 27 November 2009).
 Fisher, J. G. (2005). How to run successful incentive schemes (3rd ed.). London: Kojan.
 Fraenkel, J. R., & Wallen, N. E. (1993). How to design and evaluate research in education (2nd ed.). Boston, MA: McGraw Hill.
 Haizlip, T. (2008). Employee motivation—10 tips to boost job performance. URL (last checked 24 October 2009).
 Herzberg, F. (1966). Work and the nature of man. Cleveland, OH: World Publishing Co.
 Hoy, W. K., & Miskel, C. G. (1991). Educational administration, theory, research and practice. New York: McGraw-Hill.
 Katzell, R. A. & Thompson, D. E. (1990). Work motivation: Theory and practice. American Psychologist, 45, 144-153.
 Lawler, E. E. (1973). Motivation in work organisations. Monterey, CA: Brooks/Cole.
 Maier, N. R. (1973). Psychology in industrial organization (4th ed.). Boston, MA: Houghton Mifflin.
 Mankoe, J. (2006). Educational administration and management in Ghana (revised edition). Kumasi: Payless Publication Ltd.
 Maslow, A. (1943). A theory of human motivation, psychological review, 50, 370-396. doi:10.1037/h0054346
 Newstron, J. W., & Davis, K. (1993). Organizational behaviour, human behaviour at work. New York: McGraw-Hill.
 Robbins, S. P., & Judge, T. A. (2008). Essential organisational behaviour. Upper Saddle River, NJ: Pearson Education Inc.
 Turner, A. N., & Lawrence, P. R. (1965). Industrial jobs and the worker: An investigation of response to task attributes. Cambridge, MA: Harvard University, Graduate School of Business Division of Research.
 Vroom, V. H. (1964). Work and motivation. New York: John Wiley & Sons.
 White, A. (1998). The essential guide to developing your staff. London: Piatkus.
 Whitley, P. (2002). Motivation. Oxford: Capestone Publishing.