Open source systems: enterprise software and solutions 14th IFIP WG 2.13 International Conference, OSS 2018, Athens, Greece, June 8-10, 2018 : proceedings - Stamelos, Iōannēs G. 1959-; González-Barahoña, Jesús M.; Varlamis, Iraklis 1974-; Anagnostopoulos, Dimosthenis (Springer, 2018)