News & Comment SCIENTIFIC NOTES AND NEWS Science 17 May 1940:Vol. 91, Issue 2368, pp. 473-476DOI: 10.1126/science.91.2368.473 Article Info & Metrics eLetters PDF This is a PDF-only article. The first page of the PDF of this article appears above.
Science Vol 91, Issue 236817 May 1940 Table of Contents Print Table of Contents Back Matter (PDF) Front Matter (PDF)
