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3. Botfriends: Guided Buying: Wie mit Chatbots Maverick Buying verhindert werden kann. White paper (o.J.a)
4. Botfriends: How to Use Chatbots in Procurement. White paper (o.J.b)
5. Delke, V., Buchholz, W., Schiele, H.: Specifying roles in purchasing and supply management in the era of Industry 4.0: A Delphi study. Paper for the 28th EurOMA conference: Managing the “new normal”: The future of Operations and Supply Chain Management in unprecedented times (2021)