Regarding the technical implementation of referencing the Gold Book via the advised semantic web predicates, it needs to be mentioned that, when doing it on the axiom level, as shown in Figures and, some graphical ontology browsers might not be able to render these annotations correctly. In such cases, providing the Gold Book references via annotations on the term level, as shown in Figures and below, might be an alternative solution. Currently, there is no clear consensus on which of these two methods should be preferred. Within the OBO community, term level annotations are common using only the IAO predicate definition source, but whether to use more standard semantic web predicates instead is being discussed. We suggest opting for using axiom-level annotations whenever possible, since other metadata about the ontology term, such as its preferred label, creation date, or term status, are typically provided on the term level. Using axiom-level annotations would thus indicate more prominently that these annotations are only about the provenance of the term definition and not the ontology term itself.