Rainich, G. Y. A new kind of representation of curved space. (English) JFM 49.0551.05 American M. S. Bull. 29, 441-442 (1923). PDFBibTeX XMLCite \textit{G. Y. Rainich}, Bull. Am. Math. Soc. 29, 441--442 (1923; JFM 49.0551.05)
Rainich, G. Y. Geometry of curved space without coordinates. (English) JFM 49.0551.04 American M. S. Bull. 29, 213 (1923). PDFBibTeX XMLCite \textit{G. Y. Rainich}, Bull. Am. Math. Soc. 29, 213 (1923; JFM 49.0551.04)