@misc{HoltBuchholzdeBie2017,
  author    = {Holt, Christian and Buchholz, Wolfgang and de Bie, Holger},
  title     = {How to identify indirect material for global sourcing? Conceptualization of a portfolio matrix based on an exploratory empirical study, 26th Annual International Purchasing and Supply Education and Research Association (IPSERA) Conference: "Coping with the Future: Picking your Battles", Budapest/Balatonfured, Hungary , 2017},
  year      = {2017},
  language  = {en}
}