1. Alter S. Service system axioms that accept positive and negative outcomes and impacts of service systems. Int Conf Inf Syst. 2017;38:1–21.
2. Baget J-F. Simple conceptual graphs revisited: hypergraphs and conjunctive types for efficient projection algorithms. Int Conf on Concept Struct. 2003;2746:229–42.
3. Berge C (ed). Hypergraph: combinatorics of finite sets. Elsevier; 1989.
4. von Bertalanffy L. The history and status of general systems theory. Acad Manag J. 1972;15(4):407–26.
5. Beverungen D, Lüttenberg H, Wolf V. Recombinant service systems engineering. Bus Inf Syst Eng. 2018;21(1):50.