______CHELSEA SCIENTIFIC BOOKS______ ARRANGED ALPHABETICALLY BY AUTHOR THEORIE DER -FUNKTIONEN MEHR-ERER KOMPLEXER VERAENDER-LICHEN, By H. Behnke and P. Thullen. From the Ergebnisse der Mathematik. 1934. vii+115 pages. 5^x8j4. $3.25 LEHRBUCH DER FUNKTIONEN-THEORIE, By L. Bieberbach. Vol. 1 Fourth (latest) edition, xiv+322 pages. Vol. 2. Second (latest) edition, vi+370 pages. 5^x8^, Original price $14.80. Two vol. set $7.50 "One of the best introductions to the theory of funqtions of a complex variable. . . . scores of new problems, methods and results. Indispensable for anyone interested in modern developments." —-Bulletin of the A. M. S. KREIS UND KUGEL, By W. Blaschke. x+169 pages. 5^x8}4. $3.50 Three main topics are dealt with: The isoperi-metric properties of the circle and sphere, the (Brunn-Minkowski) theory of convex bodies, and differential-geometric properties (in the large) of convex bodies. VORLESUNGEN UBER INTEGRAL-GEOMETRIE, By W. Blaschke. 2 Vols. "elegant theory of integral invariants, with applications not only to geometric probability, but also to differential geometry, maximum and minimum problems and geometrical optics."—Bulletin of the A. M. S. Bound together with: EINFUHRUNG IN DIE THEORIE DER SYSTEMS VON DIFFERENTIALGLEI-CHUNGEN, By E. Kahler. Blaschke: Vol. 1 (2 ed.) 1936, Vol. 2 1937; Kahler: 1934. All three vols: 222 pp. 5j^x8^. Three Vols. in One $3.95 VORLESUNGEN UBER FOURIER-SCHE INTEGRALS, By S. Bochner. 1932. 237 pages. Sj^xSj^. Originally published at $6.40. $3.95 "a readable account of those parts of the subject useful for applications to problems of mathematical physics or pure analysis. The author has given in detail such of the results of the theory of functions required as are not included'in the standard treatises."