| 1926 | Essays of Revolt✓Free | Jack London | English |
| 1926 | Henry George's Progress and Poverty✓ — An Abridgement of the Economic Principles | Henry George | English |
| 1926 | History of the Conflict Between Religion and Science✓Free | John William Draper | English |
| 1926 | Imperialism✓ — The State and Revolution | Vladimir Il’ich Lenin | English |
| 1926 | Individual Liberty✓Free — Selections from the Writings of Benjamin R. Tucker | Benjamin Ricketson Tucker | English |
| 1926 | London's Essays of Revolt✓Free Collection | Jack London | English |
| 1926 | Looking Backward, 2000-1887Free | Edward Bellamy | English |
| 1926 | New Tactics in Social Conflict✓Free — Symposium [of the League for Industrial Democracy ... 1926] | Harry Wellington Laidler & Harry W. Laidler | English |
| 1926 | News from Nowhere✓Free — An Epoch of Rest; Being Some Chapters from a Utopian Romance | William Morris | English |
| 1926-01-01 | News from Nowhere or an Epoch of RestFree | William Morris | Not recorded |
| 1926-01-01 | Out of the Past✓Free — Some Revolutionary Sketches | Raymond Postgate | English |
| 1926 | Ruskin's Views of Social Justice✓Free | John Ruskin | English |
| 1926 | The a B C of Evolution✓Free | Vance Randolph | English |
| 1926 | The ABC of Astronomy✓Free | Jay Laird Burgess Taylor | English |
| 1926 | The ABC of Astronomy, by Jay L. B. Taylor✓Free | Jay L. B. Taylor | English |
| 1926 | The British General Strike✓Free — An Economic Interpretation of Its Background and Its Significance | Scott Nearing | English |
| 1926 | The Conquest of Bread✓Free | Peter Kropotkin | English |
| 1926 | The Essentials of Marx✓ — The Communist Manifesto | Karl Marx | English |
| 1926 | The Jungle✓Free | Upton Sinclair | English |
| 1926 | The Riddle of the Universe✓ | Ernst Heinrich Philipp August Haeckel | English |
| 1926 | The Socialism of Bernard Shaw✓ | Bernard Shaw & James Fuchs | English |
| 1926 | The Socialism of Shaw✓Free | George Bernard Shaw | English |
| 1926 | The Socialism of Shaw, George Bernard Shaw✓Free | Bernard Shaw | English |
| 1926-01-01 | The State✓Free — Its History and Development Viewed Sociologically | Franz Oppenheimer, John M. Gitterman & Paul Avrich Collection (Library of Congress) | English |
| 1926-01-01 | The Substance of History of Civilization in England✓ | Henry Thomas Buckle | English |
| 1926-01-01 | The Substance of History of Civilization in England, Summarized | Henry Thomas Buckle | Not recorded |
| 1926 | The Substance of History of European Morals (from Augustus to Charlemagne)✓Free | William Edward Hartpole Lecky | English |
| 1926 | The Substance of History of European Morals (from Augustus to Charlemagne) by William Edward Hartpole Lecky, Summarized by Clement Wood✓Free | William Edward Hartpole Lecky | English |
| 1926 | The Substance of the Descent Man by Charles Darwin✓ | Vance Randolph | English |
| 1926 | The Substance of the Descent of Man✓ | Vance Randolph & Charles Darwin | English |
| 1926 | The Substance of the Riddle of the Universe✓Free | Vance Randolph | English |
| 1926 | The Theory of the Leisure Class✓Free — An Economic Study of Institutions | Thorstein Veblen | English |
| 1926-01-01 | War--patriotism--peace✓Free | Leo Tolstoy (Лев Толстой) | English |
| 1926 | What Is the Single Tax?✓Free | Louis F. Post | English |
| 1926 | What's the Use of Books✓Free | Upton Sinclair | English |
| 1926 | Yerney's Justice✓Free | Ivan Cankar | English, Slovenian |
| 1926 | Yerney's Justice, by Ivan Cankar✓Free — Translated from the Slovenian (Yugoslav) by Louis Adamic | Ivan Cankar | English |
| 1927 | An American Pilgrimage✓Free — Portions of the Letters of Grace Scribner | Grace Scribner | English |
| 1927 | Basic Principles of Scientific Socialism✓ | Avraham Śim.hah Za.ks | English |
| 1927 | Company Unions, Employers' "Industrial Democracy,"✓Free | Robert Williams Dunn | English |
| 1927 | Company Unions, Employers' "Industrial Democracy." by Robert W. Dunn✓Free | Robert W. Dunn | English |
| 1927 | Dan Minturn✓Free | M. H. Hedges | English |
| 1927 | Dan Minturn, by M. H. Hedges✓Free | Hedges, M. H. b. 1888 | English |
| 1927 | Daughter of the Revolution✓Free — And Other Stories | John Reed | English |
| 1927 | Daughter of the Revolution, and Other Stories, by John Reed, Edited, with an Introduction, by Floyd Dell✓Free | John Reed | English |
| 1927 | Equitable Society and How to Create It✓Free | Warren Edwin Brokaw | English |
| 1927-01-01 | Happily Ever After | Constance Buel Burnett | Not recorded |
| 1927 | Heavenly Discourse✓ | Charles Erskine Scott Wood | English |
| 1927 | How the Soviets Work✓Free Vanguard Studies of Soviet Russia | Henry Noel Brailsford | English |
| 1927-01-01 | How the Soviets Work, (Vanguard Studies of Soviet Russia) | Henry Noel Brailsford | English |
| 1927 | Is Conscience a Crime?✓ | Norman Thomas | English |
| 1927 | Kropotkin's Revolutionary Pamphlets✓ — A Collection of Writings | Peter Kropotkin | English |
| 1927-01-01 | Looking Backward, 2000-1887✓Free | Edward Bellamy & Sylvester Baxter | English |
| 1927 | Love's Coming of Age✓Free — A Series of Papers on the Relations of the Sexes | Edward Carpenter | English |
| 1927 | Negro Labor in the United States, 1850-1925✓Free — A Study in American Economic History | Charles H. Wesley | English |
| 1927 | News from Nowhere✓Free — An Epoch of Rest, Being Some Chapters from a Utopian Romance | William Morris | English |
| 1927 | Not Guilty✓Free — A Defence of the Bottom Dog | Robert Blatchford | English |
| 1927 | Prosperity?✓ | Harry Wellington Laidler | English |
| 1927 | Prosperity? Symposium✓Free | Harry Wellington Laidler | English |
| 1927-01-01 | Proudhon's Solution of the Social Problem✓Free — Including Commentary and Exposition by Charles a. Dana and William B. Greene, Edited, with Introd. By Henry Cohen | P.-J. Proudhon | English |
| 1927-01-01 | Religion Under the Soviets✓Free Vanguard Studies of Soviet Russia | Julius F. Hecker | English |
| 1927 | Religion Under the Soviets, by Julius F. Hecker✓Free | Hecker, Julius Friedrich, b. 1881 | English |
| 1927 | Soviet Russia and Her Neighbors✓Free Vanguard Studies of Soviet Russia | Robert Page Arnot | English |
| 1927-01-01 | Soviet Russia and Her Neighbors, (Vanguard Studies of Soviet Russia) | Robert Page Arnot | Not recorded |
| 1927 | Soviet Russia and Her Neighbours✓ Vanguard Studies of Soviet Russia | Robert Page Arnot | English |
| 1927 | The a B C of Art✓Free | John Haldane Blackie | English |
| 1927 | The a B C of Biology, by Vance RandolphFree | Vance Randolph | English |
| 1927 | The a B C of Chemistry✓ | Vance Randolph | English |
| 1927 | The a B C of Geology✓Free | Allison Hardy | English |
| 1927 | The a B C of Physiology✓Free | Vance Randolph | English |
| 1927 | The a B C of Psychology✓Free | Vance Randolph | English |
| 1927 | The ABC of Art | John Haldane Blackie | English |
| 1927 | The ABC of Art, by John Haldane Blackie✓Free | John Blackie | English |
| 1927 | The ABC of Biology | Vance Randolph | English |
| 1927 | The ABC of Geology✓Free | Vance Randolph | English |
| 1927 | The ABC of History✓ | Harrison Cook Thomas & William Albert Hamm | English |
| 1927 | The ABC of Psychology | Vance Randolph | English |
| 1927 | The British General Strike✓ — An Economic Interpretation of Its Background and Its Significance | Scott Nearing | English |
| 1927 | The Child and the Home✓Free — Essays on the Rational Bringing-up of Children | B. Liber | English |
| 1927 | The Conquest of Bread✓Free | Peter Kropotkin | English |
| 1927 | The Economic Organization of the Soviet Union✓Free Vanguard Studies of Soviet Russia | Scott Nearing | English |
| 1927 | The Essentials of Marx✓ — The Communist Manifesto | Karl Marx | English |
| 1927 | The Foundations of Modern Civilization✓ A B C of History, Vol. I | Harrison Cook Thomas, William A. Hamm & William Albert Hamm | English |
| 1927 | The Great French Revolution, 1789-1793✓Free — Translated from the French by N.F. Dryhurst | Peter Kropotkin | English |
| 1927 | The Great French Revolution. 1789-1793. Transl. From the French by N.F. DryhurstFree | Petr Alekseevič Kropotkin | Not recorded |
| 1927 | The Jungle✓Free | Upton Sinclair | English |
| 1927 | The Main Stem✓Free | William Edge | English |
| 1927 | The Main Stem by William Edge✓Free | William Edge | English |
| 1927 | The Profits of Religion✓Free — An Essay in Economic Interpretation | Upton Sinclair | English |
| 1927-01-01 | The Story of Civil Liberty in the United States✓Free | Leon Whipple | English |
| 1927 | The Substance of History of European Morals | William Edward Hartpole Lecky | English |
| 1927 | The Substance of History of European Morals from Augustus to Charlemagne✓ | William Edward Hartpole Lecky | English |
| 1927 | The Substance of the Riddle of the Universe✓Free | Vance Randolph | English |
| 1927 | The Theory of the Leisure Class✓Free — An Economic Study of Institutions | Thorstein Veblen | English |
| 1927 | The War Myth in United States History✓Free | C. H. Hamlin | English |
| 1927-01-01 | Village Life Under the Soviets✓Free Vanguard Studies of Soviet Russia | Karl Borders | English |
| 1927 | Village Life Under the Soviets, by Karl Borders✓Free | Karl Borders | English |
| 1927 | War, Patriotism, Peace✓ | Lev Nikolaevič Tolstoj | English |
| 1927 | Wells' Social Anticipations✓Free | Herbert George Wells | English |
| 1927 | Wells' Social Anticipations, H.G. Wells, Edited, with Introduction, by Harry W. Laidler✓Free | H. G. Wells | English |
| 1927 | What Is Cooperation?✓ — A Discussion of the Consumers' Cooperative Movement, Its Principles, Methods and Accomlishments | James Peter Warbasse | English |
| 1927 | What Is Cooperation? A Discussion of the Consumers' Cooperative Movement, Its Principles, Methods and Accomplishments✓Free | James Peter Warbasse | English |
| 1927 | What Is Mutualism✓Free | Clarence Lee Swartz & Mutualist Associates | English |
| 1927 | What Is Mutualism? By Clarence Lee Swartz, in Collaboration with the Mutualist Associates✓Free | Clarence Lee Swartz | English |
| 1927 | What's so and What Isn't✓Free | John M. Work | English |
| 1927 | What's so and What Isn't, by John M. Work✓Free | John McClelland Work | English |
| 1927 | What's the Use of Books?✓ | Upton Sinclair | English |
| 1927 | Where Is Civilization Going?✓Free — By Scott Nearing | Scott Nearing | English |
| 1928 | Civilization in Transition (1789-1870)✓Free The ABC of History | Harrison Cook Thomas | English |
| 1928 | Civilization in Transition, 1789-1870 by H.C. Thomas and W.A. Hamm✓ The ABC of History, v. 2 | Harrison Cook Thomas | English |
| 1928 | Don't Tread on Me✓Free — A Study of Aggressive Legal Tactics for Labor | Clement Wood | English |
| 1928 | Extraordinary Women✓ — Theme and Variations | Compton Mackenzie | English |
| 1928 | Health Work in Soviet Russia✓Free Vanguard Studies of Soviet Russia | Anna J. Haines | English |
| 1928-01-01 | Heavenly Discourse | Charles Erskine Scott Wood | Not recorded |
| 1928 | How the Old Woman Got Home✓ | Matthew Phipps Shiel | English |
| 1928 | How the Soviets Work✓ Vanguard Studies of Soviet Russia | Henry Noel Brailsford | English |
| 1928 | Liberty Under the Soviet✓ Coll. Vanguard Studies of Soviet Russia | Roger N. Baldwin | English |
| 1928 | Liberty Under the Soviets✓Free Vanguard Studies of Soviet Russia | Roger Nash Baldwin | English |
| 1928-01-01 | London's Essays of Revolt | J. London | English |
| 1928 | Lost Wolf✓ | Frederick Faust | English |
| 1928 | Love's Coming of Age✓Free — A Series of Papers on the Relations of the Sexes | Edward Carpenter | English |
| 1928-01-01 | Our Cuban Colony✓Free — A Study in Sugar American Imperialism | Leland Hamilton Jenks | English |
| 1928 | Our Own Times✓Free The ABC of History | Harrison Cook Thomas | English |
| 1928 | Our Own Times, by H.C. Thomas and W.A. Hamm✓Free | Harrison Cook Thomas | English |
| 1928 | Soviet Trade Unions✓Free Vanguard Studies of Soviet Russia | Robert Williams Dunn | English |
| 1928 | The a B C of Evolution, by Vance Randolph✓Free | Vance Randolph | English |
| 1928-01-01 | The Americans in Santo Domingo✓Free American Imperialism | Melvin Moses Knight | English |
| 1928 | The Ballad of Reading Gaol✓Free | Oscar Wilde & Lynd Ward | English |
| 1928 | The Bankers in Bolivia✓Free — A Study in American Foreign Investment Studies in American Imperialism | Margar exander Marsh | English |
| 1928 | The Bankers in Bolivia Study in American Foreign Investment✓Free American Imperialism | Margar exander Marsh | English |
| 1928 | The Jews and Other Minor Nationalities Under the Soviets✓Free Vanguard Studies of Soviet Russia | Avrahm Yarmolinsky | English |
| 1928 | The New Schools of New Russia✓Free Vanguard Studies of Soviet Russia | Lucy Langdon Williams Wilson | English |
| 1928 | The Profits of Religion✓Free — An Essay in Economic Interpretation | Upton Sinclair | English |
| 1928 | The Remedy for Overproduction and Unemployment✓ | Hugo Bilgram | English |
| 1928 | The Shadowy Thing | H. B. Drake | English |
| 1928 | The State✓ — Its Historyand Developed Viewed Sociologically | Franz Oppenheimer | English |
| 1928 | The State, Its History and Development Viewed Sociologically✓Free | Franz Oppenheimer | English |
| 1928 | Vanguard Studies of Soviet Russia✓ — (Edited by Jerome Davis) | Jerome Davis | Not recorded |
| 1928-01-01 | What Is Socialism?✓Free | Jessie Wallace Hughan | English |
| 1928 | What Is Socialism? By Jessie Wallace HughanFree | Jessie Wallace Hughan | English |
| 1928 | What Philosophy Is✓ | Harold A. Larrabee | English |
| 1928 | Woman in Soviet Russia✓Free Vanguard Studies of Soviet Russia | Jessica Smith | English |
| 1928 | Women in Soviet RussiaFree | Jessica Smith | English |
| 1928 | Women in the Soviet Russia | Jessica Smith | Not recorded |
| 1929 | "Farmer, Have You a Daughter Fair?"✓Free — A Traveling Salesman Meets the Mamselles from Armentières | Mike Wallach | English |
| 1929 | "Farmer, Have You a Daughter Fair?" a Traveling Salesman Meets the Mamselles from Armentières, by Mike Wallach✓Free | Mike Wallach | English |
| 1929 | A Book of Tales✓Free — Being Some Myths of the North American Indians | Charles Erskine Scott Wood | English |
| 1929 | A Great Love✓Free | Alexandra Kollontai | English, Russian |
| 1929 | Black America✓Free | Scott Nearing | English |
| 1929 | Cold Steel✓Free | Matthew Phipps Shiel | English |
| 1929 | Cold Steel, by M. P. Shiel✓Free | M. P. Shiel | English |
| 1929 | Dr. Krasinki's Secret, by M.P. Shiel✓Free | M. P. Shiel | English |
| 1929 | Dr. Krasinski's Secret✓Free | Matthew Phipps Shiel | English |
| 1929 | Evelyn✓ — Something More than a Story | James Francis Dwyer | English |
| 1929 | Five Women on a Galley✓Free | Suzanne Normand | English |
| 1929 | Heavenly Discourse | Charles Erskine Scott Wood | English |
| 1929 | How Like a God✓ | Rex Stout | English |
| 1929-01-01 | Imperialism✓ — The State and Revolution | Vladimir Il’ich Lenin | English |
| 1929-01-01 | In the Reign of Rothstein✓Free | Donald Henderson Clarke | English |
| 1929 | John D.✓Free — A Portrait in Oils | John K. Winkler | English |
| 1929 | Louis Beretti✓ — A Novel | Donald Henderson Clarke | English |
| 1929 | Love's Pilgrimage✓Free — A Novel | Upton Sinclair | English |
| 1929 | Now and After✓ — The ABC of Communist Anarchism | Alexander Berkman | English |
| 1929 | Pioneers of Freedom✓Free | McAlister Coleman | English |
| 1929-01-01 | Progress and Poverty✓Free | Henry George | English |
| 1929 | Rattling the Cup on Chicago Crime✓Free | Edward Dean Sullivan | English |
| 1929 | Sold Out!✓ | Edward Dean Sullivan | English |
| 1929-01-01 | That Devil Wilkes✓Free | Raymond Postgate | English |
| 1929 | The Devil Wilkes | R. W. Postgate | English |
| 1929-01-01 | The Dissenting Opinions of Mr. Justice Holmes✓Free — Arranged, with Introductory Notes | Oliver Wendell Holmes Jr. | English |
| 1929 | The Dissenting Opinions of Mr. Justice Holmes by Dr. George W. Kirchwey | George W. Kirchwey | English |
| 1929-01-01 | The Economic Organization of the Soviet UnionFree | Jack Nearing Scott And Hardy | Not recorded |
| 1929 | The Great French Revolution, 1789-1793Free — By P. a. Kropotkin. Translated from the French by N. F. Dryhurst | Kropotkin, Petr Alekseevich, kniazʹ | English |
| 1929-01-01 | The Jungle✓Free | Upton Sinclair | English |
| 1929 | The Letters of Sacco and Vanzetti✓ | Nicola Sacco | English |
| 1929 | The Perfect Baby✓Free | Claire Morton | English |
| 1929 | The Perfect Baby, by Claire Morton, with a Foreword by Dr. Murray H. BassFree | Claire Morton | English |
| 1929 | The Plays of Ferenc Molnar✓Free | Ferenc Molnár | English |
| 1929 | The Poet in the Desert✓Free | Charles Erskine Scott Wood | English |
| 1929 | The Socialism of Our Times✓ — A Symposium | Harry Elmer Barnes | English |
| 1929 | The Story of Al Capone | Edward D. Sullivan | Not recorded |
| 1929-01-01 | The Twilight of Christianity✓Free | Harry Elmer Barnes | English |
| 1929 | What Is Communist Anarchism?✓Free | Alexander Berkman | English |
| 1929-01-01 | Why We Fought✓Free | C. Hartley Grattan | English |
| 1929 | Wings, the a B C of Flying, by W. Lockwood Marsh✓Free | W. Lockwood Marsh | English |
| 1930 | A Marriage to India✓Free | Frieda Mathilda Hauswirth Das | English |
| 1930-01-01 | An East Side Epic✓Free — The Life and Work of Meyer London | Hillel Rogoff | English |
| 1930 | Chicago Surrenders✓Free | Edward Dean Sullivan | English |
| 1930 | Chicago Surrenders Edward Dean SullivanFree — A Sequel to "Rattling the Cup on Chicago Crime".9 250 | Edward Dean Sullivan | English |
| 1930 | Dark Power✓Free | Elisabeth Sanxay Holding | English |
| 1930 | Dog Lane✓Free — Translated from the Russian by N.R. Wreden | Lev Ivanovich Gumilevskiǐ | English |
| 1930 | Ex-"it"✓Free | Edward Dean Sullivan | English |
| 1930 | Grim Youth, by John Held, Jr., with Illustrations by the Author✓Free | John Held | English |
| 1930 | I'll Tell My Big Brother✓Free | Edward Dean Sullivan | English |
| 1930 | John Held, Jr.'s Dog Stories✓ | John Held | English |
| 1930 | Liberty Under the Soviets✓ Vanguard Studies of Soviet Russia | Roger Nash Baldwin | English |
| 1930-01-01 | Morgan the Magnificent✓Free — The Life of J. Pierpont Morgan (1837-1913) | John K. Winkler | English |
| 1930 | Morgan the Magnificent, the Life of J. Pierpont Morgan, 1837-1913, by John K. Winkler✓ | John Kennedy Winkler | English |
| 1930 | Morgan the Magnificient✓ — The Life of J. Pierpont Morgan (1837-1913) | John Kennedy Winkler | English |
| 1930 | O Splendid Sorcery✓Free | James Francis Dwyer | English |