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In addition to being a bookseller, John Martin was also a librarian. He worked at the Bodleian Library in Oxford, England, from 1831 to 1838. During his time there, he was responsible for cataloging the library's collection of books and manuscripts. He also wrote a number of books on librarianship, including "A Manual of Library Economy" (1839) and "The British Museum Library: A Guide for Readers" (1842).