Both volumes of classic text on trigonometric series, with a foreword by Robert Fefferman.This is the third edition of Professor Zygmund's classsic Trigonometric Series, now featuring a foreword by Elias Stein. Both volumes of the 1959 edition are here bound as one. Volume I, containing the completely re-written material of the original work, deals with trigonometric series and Fourier series. Volume II provides much material previously unpublished in book form. The rigorous treatment of trigonometric and Fourier series, and related branches of pure mathematics presented here is a reference work of enduring value for mathematicians at graduate level and above.This is the third edition of Professor Zygmund's classsic Trigonometric Series, now featuring a foreword by Elias Stein. Both volumes of the 1959 edition are here bound as one. Volume I, containing the completely re-written material of the original work, deals with trigonometric series and Fourier series. Volume II provides much material previously unpublished in book form. The rigorous treatment of trigonometric and Fourier series, and related branches of pure mathematics presented here is a reference work of enduring value for mathematicians at graduate level and above.Professor Zygmund's Trigonometric Series, first published in Warsaw in 1935, established itself as a classic. It presented a concise account of the main results then known, but on a scale that limited the amount of detailed discussion possible. A greatly enlarged second edition (Cambridge, 1959) published in two volumes took full account of developments in trigonometric series, Fourier series, and related branches of pure mathematics since the publication of the original edition. These two volumes, bound together with a foreword from Robert Fefferman, outline the significance of this text. Volume I, containing the completely re-written material of the original work, deals with trigonometric series and Fourier series. Volume II provides much ml£(