The Numismatist - Google Books

http://books.google.de/books?ei=2rQNTsQM0fKyBuOCjIMP&ct=result&id=xDdOAAAAYAAJ&dq=speso+esperanto&q=speso++#search_anchor

Vols. 24-52 include the Proceedings of the American Numismatic Association Convention, 1911-39.