As part of preliminary studies for the development of a digital library, we have studied the possibility of using the UMLS Information Sources Map (ISM) database to provide the means to connect and map different terminologies, as well as to facilitate access to available information sources. The main issues discussed are the indexing of and connection to relevant online sources. We found the features of the ISM to be consistent with the need to support automated source selection and retrieval. However, attention should be paid to three aspects of the information: granularity, completeness, and accuracy. We found the ISM to be potentially useful; however, significant modifications will be required if the ISM is to be able to support automated source selection and retrieval.