Ziegler, PatrickSturm, ChristophDittrich, Klaus R.Vossen, GottfriedLeymann, FrankLockemann, PeterStucky, Wolffried2019-10-112019-10-1120053-88579-394-6https://dl.gi.de/handle/20.500.12116/28274Ontology languages to represent ontologies exist in large numbers, and users who want to access or reuse ontologies can often be confronted with a language they do not know. Therefore, due to their great number, ontology languages are nowadays themselves a source of heterogeneity. In this paper, we present the SIRUP Ontology Query API (SOQA) that was developed for the SIRUP approach to semantic data integration [ZD04b]. SOQA is an ontology languageand platform-independent API for query access to ontological metadata and data that can be represented in a variety of ontology languages. Based on SOQA, we provide SOQA-QL, an SQL-like query language that supports declarative queries against ontological metadata and data, and the SOQA Browser, a tool to graphically inspect all ontology information that can be accessed through SOQA.enText/Conference Paper1617-5468