Modern Problems of Management: Economics, Education, Health Care and Pharmacy : Conference Proceedings of the 5th International Scientific Conference, October 26-29, 2017, Opole, Poland. Pp. 79-81. - Opole : The Academy of Management and Administration, 2017 ; Modern Problems of Management: Economics, Education, Health Care and Pharmacy International Scientific Conference / Ciepaj Marian. ISBN 978-83-62683-23-9