Problems and Theorems in Analysis I by Polyà/Szegö is also available in the Classics in Mathematics series (3-540-63640-4).
Very few mathematical books are worth translating 50 years after their original publication. Polyá-Szegö is one! It was published in German by Springer in 1924, its English edition was widely acclaimed when it appeared from 1972. In the past more of the leading mathematicians proposed and solved problems than today. Their collection of the best in analysis is a heritage of lasting value.
George Polya
Fourier series calculus maximum minimum number theory
From the reviews: "... In the past, more of the leading mathematicians proposed and solved problems than today, and there were problem departments in many journals. Pólya and Szego must have combed all of the large problem literature from about 1850 to 1925 for their material, and their collection of the best in analysis is a heritage of lasting value. The work is unashamedly dated. With few exceptions, all of its material comes from before 1925. We can judge its vintage by a brief look at the author indices (combined). Let's start on the C's: Cantor, Carathéodory, Carleman, Carlson, Catalan, Cauchy, Cayley, Cesàro,... Or the L's: Lacour, Lagrange, Laguerre, Laisant, Lambert, Landau, Laplace, Lasker, Laurent, Lebesgue, Legendre,... Omission is also information: Carlitz, Erdös, Moser, etc."
-Bull.Americ.Math.Soc.
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