Piorunowska-Kokoszko, Joanna. “GROUP PURCHASING ORGANIZATION (GPO) AS A MEANS OF BUSINESS COSTS SAVINGS”. Journal of Positive Management 6, no. 1 (September 13, 2015): 56–70. Accessed July 18, 2024. https://apcz.umk.pl/JPM/article/view/JPM.2015.005.