The digitization of botanical collections has increasingly brought biodiversity research activities online. In order to make these data usable in the most efficient way, various obstacles have to be overcome. One such obstacle is a lack of ability to integrate information from other sources. While agreed upon, machine-understandable data standards such as ABCD have resulted in concepts that can already be described semantically, yet they are often transmitted as free-text information. The utilization of identifers for collectors has created opportunities for the integration of data from external information systems. However, since the identifers used are not standardized and vary from institution to institution, this work aims to develop a web service demonstrating that this problem can be overcome by applying appropriate Linked Data methods on centralized knowledge bases such as Wikidata. After eliciting requirements from participating CETAF institutions, an API was designed and implemented on this basis that can integrate biographic, bibliographic, and collection data into a single semantic file format by leveraging multiple endpoints. Thus, the work shows that diverse identifers used in collection databases do not have to be a problem. Moreover, missing IDs for important information sources such as Wikidata can be found and used. Heterogeneous data from different sources can be merged using previously defined mappings, although such data may not be available in semantic formats. Further sources of information could thus be added in the future. Furthermore, a future focus on annotated geographic identifers is also conceivable to additionally integrate semantic data on collection object found locations.
