I thought Earth Interactions was produced with SGML, but I can view full text as either HTML or PDF?
Earth Interactions is coded in Standard Generalized Mark-up Language (SGML), which is an international standard, platform-independent coding of information that supports a wide variety of special characters and forms, including complex mathematics. For the first three and a half years the journal was delivered in SGML and PDF in anticipation of robust SGML viewers on the Web. Those have not yet materialized (though XML is emerging) and the original SGML viewer, Panorama, is no longer well-supported. Therefore, EI has been re-engineered to use an SGML-to-HTML conversion on the fly for Web delivery.