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2. Bangladesh bureau of statistics. Ministry of planning, the government of People’s Republic of Bangladesh, pp. 81 & 327. Dhaka, Bangladesh.
3. Bangladesh tea research institute, the government of people’s republic of Bangladesh, pp. 94-98, Srimangal, Moulvibazar, Bangladesh.
4. Box, G.E.P., Jankins, G.W, and Reinsel G. (1994). “Time Series Analysis, Forecasting, and Control”, edition, Englewood Cliffs, N.J.; Prentice-Hall.
5. Brokwell P. J. and R. A. Davis (1996) “Introduction to Time Series and Forecasting, Springer, New York.