There are nice scales already developed to measure authenticity. The following is one of the good ones: 

Napoli, J., Dickinson, S. J., Beverland, M. B., & Farrelly, F. (2014). Measuring consumer-based brand authenticity. Journal of Business Research, 67(6), 1090-1098.

Best wishes!

Thank you, Doctor, Kaleel Rahman for the useful answer

accept my great respect

Here is one more paper 

Morhart, Felicitas, et al. "Brand authenticity: An integrative framework and measurement scale." Journal of Consumer Psychology 25.2 (2015): 200-218.

http://www.novasbe.unl.pt/images/novasbe/files/INOVA_Seminars/lucia.pdf

Thank you, Dr. Samuel, I will go through this article.

Regards

Sorry to mention. The question is not clear and specific.

The following papers should be helpful: 

• Erickson, R. J. (1995). The importance of authenticity for self and society. Symbolic Interaction, 18, 2, pp. 121-144.
• Gardner, W. L., Cogliser, C. C., Davis, K. M. and Dickens, M. P. (2011). Authentic leadership: A review of the literature and research agenda. The Leadership Quarterly, 22, 6, pp. 1120-1145.
• George, B., Sims, P., McLean, A. N. and Mayer, D. (2007). Discovering your authentic leadership. Harvard Business Review, 85, 2, pp. 129-138.
• Goffee, R. and Jones, G. (2005). Managing authenticity. Harvard Business Review, 83, 12, pp. 85-94.