Of the products provided on this page, only "Publications" have been peer-reviewed and may be considered final products suitable for quotation or citation. All other products ("Newsletters, Presentations, Reports, Protocols") contain incomplete or preliminary analyses of data that may change in the future; conclusions are not final and also subject to change. If you wish to cite these non-peer-reviewed products, please contact the authors first.

Under "Publications" we provide scanned PDF documents of original articles published in peer-reviewed journals or conference proceedings. As government employees we are not bound by copyright laws on the distribution of these articles. However, PDF documents are not nearly so clear and crisp as the original articles (particularly graphics), and we still recommend that you view the originals in the journal, or ask us for reprints-- which we will be happy to send you.

If you have any questions or concerns, please contact: John_Piatt@usgs.gov