Nelson, E. J. Whitehead and Russell’s theory of deduction as a non-mathematical science. (English) Zbl 0009.33706 Bull. Am. Math. Soc. 40, 478-486 (1934). PDFBibTeX XMLCite \textit{E. J. Nelson}, Bull. Am. Math. Soc. 40, 478--486 (1934; Zbl 0009.33706) Full Text: DOI
Nelson, Everett J. Deductive systems and the absoluteness of logic. (English) Zbl 0006.09704 Mind, New Ser. 42, No. 165, 30-42 (1933). PDFBibTeX XMLCite \textit{E. J. Nelson}, Mind, New Ser. 42, No. 165, 30--42 (1933; Zbl 0006.09704) Full Text: DOI