Philip Kotler (1967). Marketing Management. Published by Pearson Education 2011.
Gupta, SP. & Gupta,M.P (2010). Business Statistics. Published by Sultan Chand & Sons 2019.
Kothari,C.R (1985). Research Methodology: Methods and Techniques (Second Revised Edition). Published by New Age International 2004.
Mangal,S.K (2004). Statistics in Psychology and Education. Published by PHI hearing Pvt. Ltd. 2002.