Originally published in 1915 as number eighteen in the Cambridge Tracts in Mathematics and Mathematical Physics series, and here reissued in its 1952 reprinted form, this book contains a condensed account of Dirichlet's Series, which relates to number theory. This tract will be of value to anyone with an interest in the history of mathematics or in the work of G. H. Hardy.

Marcel Riesz (1886-1969) was the younger of the famed pair of mathematicians and brothers. Although Hungarian he spent most of his professional life in Sweden. He worked on summability theory, analytic functions, the moment problem, harmonic and functional analysis, potential theory and the wave equation. The depth of his research and the clarity of his writing place his work on the same level as that of his brother Frederic Riesz. This edition of his Collected Papers contains most of Marcel Riesz's published papers with the exception of a few papers in Hungarian that were subsumed into later books. It also includes a translation by J. Horvath of Riesz's thesis on summable trigonometric series and summable power series. They are thus a valuable reference work for libraries and for researchers.

Marcellliesz's lectures delivered on October 1957 -January 1958 at the Uni versity of Maryland, College Park, have been previously published only infor mally as a manuscript entitled CLIFFORD NUMBERS AND SPINORS (Chap ters I - IV). As the title says, the lecture notes consist of four Chapters I, II, III and IV. However, in the preface of the lecture notes lliesz refers to Chapters V and VI which he could not finish. Chapter VI is mentioned on pages 1, 3, 16, 38 and 156, which makes it plausible that lliesz was well aware of what he was going to include in the final missing chapters. The present book makes lliesz's classic lecture notes generally available to a wider audience and tries somewhat to fill in one of the last missing chapters. This book also tries to evaluate lliesz's influence on the present research on Clifford algebras and draws special attention to lliesz's contributions in this field - often misunderstood."

Marcellliesz's lectures delivered on October 1957 -January 1958 at the Uni versity of Maryland, College Park, have been previously published only infor mally as a manuscript entitled CLIFFORD NUMBERS AND SPINORS (Chap ters I - IV). As the title says, the lecture notes consist of four Chapters I, II, III and IV. However, in the preface of the lecture notes lliesz refers to Chapters V and VI which he could not finish. Chapter VI is mentioned on pages 1, 3, 16, 38 and 156, which makes it plausible that lliesz was well aware of what he was going to include in the final missing chapters. The present book makes lliesz's classic lecture notes generally available to a wider audience and tries somewhat to fill in one of the last missing chapters. This book also tries to evaluate lliesz's influence on the present research on Clifford algebras and draws special attention to lliesz's contributions in this field - often misunderstood."