Note: These are composed of several large .gif files, so they may take several minutes to display. If some of the pages come out as little squares with an X in the middle, right click on them and hit "show picture". To print the first two of these, set your Page Setup to landscape with .5" margins.
Original Einstein-Straus Paper
A. Einstein and E.G. Straus, Ann. Math. Vol. 47 (1946) p.731
Einstein's Generalized Bianchi Identities Paper
A. Einstein, Canadian Journal of Mathematics, Vol. 2, (1950), p.120
An excerpt from Einstein's "autobiography"
Albert Einstein: Philosopher-Scientist (edited by P. A. Schilpp), (1949)
Original Schrodinger Affine Field Theory Paper
E. Schrodinger, Proceedings of the Royal Irish Academy, Vol. 51A, (1947) p. 163

Some good books on the subject are presently available at Amazon.com:
E. Schrodinger, "Space Time Structure" (Cambridge University Press, London, 1950)
A. Einstein, "The Meaning of Relativity", 5th edition, revised (Princeton University Press, Princeton, NJ, 1956)
P. A. Schilpp, "Albert Einstein: Philosopher-Scientist" (Open Court Publishing, Peru IL, 1949)