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• The technical challenges in OOP application across the European Union and the TOOP OOP architectureTepandi, Jaak; Rotuna, Carmen; Sellitto, Giovanni Paolo; Fieten, Sander; Prentza, AndrianaThe once-only principle : The TOOP project2021 / p. 141−163 https://doi.org/10.1007/978-3-030-79851-2_8 https://www.scopus.com/sourceid/25674 https://www.scopus.com/record/display.uri?eid=2-s2.0-85109977228&origin=inward&txGid=1443347572a4d79cb5ea10d86235e123 https://jcr.clarivate.com/jcr-jp/journal-profile?journal=LECT%20NOTES%20ARTIF%20INT&year=2005 https://www.webofscience.com/wos/woscc/full-record/WOS:000894547800010