EINSTEIN, Albert, & Walther Mayer.
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Darstellung der Semi-Vektoren als Gewöhnliche Vektoren von besonderem Differentiations Charakter. First edition, offprint issue, of the fourth and final paper on Einstein and Mayer's semi-vectors, in which they aimed to incorporate the Dirac equation into the general theory of relativity. This last article "was presented foremost as an exercise with exclusively mathematical appeal" (Van Dongen, p. 106).
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