1. Wilson JR, Corlett EN. Evaluation of human work; a practical ergonomics methodology. 2nd ed. London, UK: Taylor & Francis; 1995.
2. Astrand P, Rodahl K. Textbook of work physiology. 3rd ed. New York, NY, USA: McGraw-Hill; 1986.
3. Das D, Das A. Statistics in biology and psychology. Calcutta, India: Academic; 1993.