Leveraging on prior work should be part of any topic map project.
Building topic maps with subject headings? See: Making topic maps from Subject Headings, a slide pack from Motomu Naito, a regular contributor in the topic maps community.
Project is using NDLSH 2008 (National Diet Library Subject Headings, subject headings 17,953), BSH4 (Basic Subject Headings, Japanese Library Association, subject headings, 7847), LCSH (Library of Congress Subject Headings, subject headings, 372,399).
Slides describe organizing Wikipedia using subject headings, merging subjects with subject headings, and, using LSCH subjects as a bridges to map between subject headings in different languages.
Forward to your local library researcher.