MC CLAVE, James T., George P. BENSON and Terry SINCICH. Statistics for Business and Economics. 12th ed. Upper Saddle River, New Jersey: Prentice Hall, 2014. ISBN 9781292023298 .
HYNDMAN, Rob J. and George ATHANASOPOULOS. Forecasting: principles and practice. 2nd edition. Melbourne: OTexts, 2018. ISBN 978-0-9875071-1-2.
Critical raw materials [online]. Available from: https://ec.europa.eu/growth/sectors/raw-materials/specific-interest/critical_en
ANDERSON, David Ray, Dennis J. SWEENEY and Thomas Arthur WILLIAMS. Modern business statistics with Microsoft Office Excel. 5th ed. Stamford: Cengage Learning, 2015. ISBN 978-1-305-08218-2.