Together 11 pages, 4to and 8vo, one letter with portion of lower blank margin excised." /> EINSTEIN, ALBERT. Four autograph letters signed ("Papa") to Hans Albert Einstein, Berlin and n.p. [probably Berlin], 25 January 1915 - 23 December 1915 and n.d. <I>Together 11 pages, 4to and 8vo, one letter with portion of lower blank margin excised.</I> | Christie's