Bernhard Riemann (1826–1866) is widely regarded as one of the leading mathematicians of the nineteenth century. He developed Riemannian geometry which is the basis for Einstein’s theory of gravitation. He also developed important theories relating to complex analysis, real analysis, number theory, and mathematical physics. A classic tote bag that'll withstand whatever you throw in it, from books to groceries! • 100% bull denim cotton construction • Dimensions: 14 ⅜” x 14” (36.5 cm x 35.6 cm) • Dual handles