http://www.rssboard.org/rss-specification 720 XTF Search Results (f4-format=Book;f5-subject=Tariff -- United States;f6-subject=Copper industry and trade -- United States) http://catalog.wrhs.org/collections/search?f4-format%3DBook;f5-subject%3DTariff%20--%20United%20States;f6-subject%3DCopper%20industry%20and%20trade%20--%20United%20States Results for your query: f4-format=Book;f5-subject=Tariff -- United States;f6-subject=Copper industry and trade -- United States Thu, 01 Jan 1970 12:00:00 GMT Letter of Henry Martin, Esq. ... to the Senate of the United States: in opposition to the bill increasing the duty on imported copper ores. Martin, Henry. http://catalog.wrhs.org/collections/view?docId=marc/skclmarc202890322046876.mrc http://catalog.wrhs.org/collections/view?docId=marc/skclmarc202890322046876.mrc Thu, 01 Jan 1970 12:00:00 GMT