Products & Materials Products & Materials Science 09 Dec 1988:Vol. 242, Issue 4884, pp. 1456DOI: 10.1126/science.242.4884.1456 Article Info & Metrics eLetters PDF This is a PDF-only article. The first page of the PDF of this article appears above.
Science Vol 242, Issue 488409 December 1988 Table of Contents Print Table of Contents Back Matter (PDF) Ed Board (PDF) Front Matter (PDF)