For an extensive listing of books in the tri-colleges about twentieth-century Japan, see the course guide for Japanese Civilization prepared by James Gulick.
Use the Tripod catalog to look for other relevant books owned by Haverford, Bryn Mawr and Swarthmore.
To find materials on a topic, try doing a keyword search in Tripod to find relevant materials
(west* or europe*) tokugawa* [Keyword search]
and then use the subject headings assigned to those titles to find more material:
japan foreign relations 1600-1868 [Subject Heading]
dutch japan [Subject Heading]
Use WorldCat to find books not held by the tri-college libraries.