Research index·Journal articleItemsScience·21 Mar 1941DOI10.1126/science.93.2412.10.sJournal articleItemsScience · 1941 · SubscriptionDOI10.1126/science.93.2412.10.sReadRead at the publisherSaveCiteAdd to literature reviewPaywalledThe full text is at the publisherOpen it at the publisher to read it.Read at the publisherDiscussionAdd to the discussionTopicsComputer scienceRelated papersMoreDetailsPublished, publisher, issueSuggest a correction or report
