Recently the copyright
of Ulysses expired and there are images of the book at Internet with
warnings about its origin and the care to be taken when it is used.
I'm using at Internet an image that Planet offers and warns that comes from Australia where there is no longer copyright for this work. I am setting this version with the 1961 above. I have decided to center around this 1961 partly because it was the one I had with me for more than 30 years, partly because when we deepen more about this issue, for pure and simple text, it seems to me the most appropriate.
Many intellectuals who are dedicated to Ulysses study do it referring to the first American edition of 1934. Others with the Gabler's Critical and Synoptic. Others with the Gabler corrected. The Gifford 2nd edition which I am using uses the corrected Gabler of 86. Blamires uses the corrected and the Oxford University Press.
Since the information is available in the edition I'm using, I will indicate in brackets () the number of the original edition of pages of 1934, at the last word of the corresponding page there and between brackets  the corrected edition number and reset in 1961 Vintage books, which is what I'm using and I consider as a reference.
In the United States there is a preference
for Gabler editions explained below.
As there are copyright to translations made for the Portuguese, I'll just comment on something I seem relevant when resolving the issue of copyright.
Readers are encouraged to have at hand translations in Portuguese, or their own language, and feel like to what the translators dealt with compared to what is stated herein and what is the validity of the "corrected editions."
The first edition of Ulysses, with 1000 copies, was issued by Sylvia Beach, Shakespeare and Company in Paris on February 2, 1922. In the United States, there was the Roth pirate edition, published in New York in 1929. Other notable editions in English were:
1 - Odyssey Press de 1932
(including some revisions generally assigned to Gilbert Stuart and therefore
consider by many as the most accurate);
2 - Random House Edition of 1934;
3 - Bodley Head in England, or UK, in 1936;
4 - Revised Bodley Head Edition of 1960;
5 - The 1961 Random House Vintage Books, which is being used in this job and
6 -Ulysses: A Critical and Synoptic Edition of 1984
7 - Gabler 1986 corrected edition
8 - Oxford University Press (Ulysses: The 1922 text) from Jeri Johnson
For details, see the following at the Indiana University web:
Gabler's "Corrected edition"
Hans Walter Gabler's 1984 edition was the most sustained attempt to produce a corrected text, but it received much criticism, most notably from John Kidd. Kidd's main theoretical criticism is of Gabler's choice of a patchwork of manuscripts as his copy-text (the base edition with which the editor compares each variant), but this fault stems from an assumption of the Anglo-American tradition of scholarly editing rather than the blend of French and German editorial theories that actually lay behind Gabler's reasoning. The choice of a multiple copy-text is seen to be problematic in the eyes of some American editors, who generally favour the first edition of any particular work as copy-text. Less subject to differing national editorial theories, however, is the claim that for hundreds of pagesabout half the episodes of Ulyssesthe extant manuscript is purported to be a 'fair copy' which Joyce made for sale to a potential patron. (As it turned out, John Quinn, the Irish-American lawyer and collector, purchased the manuscript.) Diluting this charge somewhat is the fact that the theory of (now lost) final working drafts is Gabler's own. For the suspect episodes, the existing typescript is the last witness. Gabler attempted to reconstruct what he called 'the continuous manuscript text', which had never physically existed, by adding together all of Joyce's accretions from the various sources. This allowed Gabler to produce a 'synoptic text' indicating the stage at which each addition was inserted. Kidd and even some of Gabler's own advisers believe this method meant losing Joyce's final changes in about two thousand places. Far from being 'continuous', the manuscripts seem to be opposite. Jerome McGann describes in detail the editorial principles of Gabler in his article for the journal Criticism, issue 27, 1985. In the wake of the controversy, still other commentators charged that Gabler's changes were motivated by a desire to secure a fresh copyright and another seventy-five years of royalties beyond a looming expiration date.
In June 1988 John Kidd published 'The Scandal of Ulysses' in the New York Review of Books, charging that not only did Gabler's changes overturn Joyce's last revisions, but in another four hundred places Gabler failed to follow any manuscript whatever, making nonsense of his own premises. Kidd accused Gabler of unnecessarily changing Joyce's spelling, punctuation, use of accents, and all the small details he claimed to have been restoring. Instead, Gabler was actually following printed editions such as that of 1932, not the manuscripts. More sensationally, Gabler was found to have made genuine blunders, the most famous being his changing the name of the real-life Dubliner Harry Thrift to 'Shrift' and cricketer Captain Buller to 'Culler' on the basis of handwriting irregularities in the extant manuscript. (These 'corrections' were undone by Gabler in 1986.) Kidd stated that many of Gabler's errors resulted from Gabler's use of facsimiles rather than original manuscripts.
In December 1988, Charles Rossman's 'The New Ulysses: The Hidden Controversy' for the New York Review revealed that Gabler's own advisers felt too many changes were being made, but that the publishers were pushing for as many alterations as possible. Then Kidd produced a 174-page critique that filled an entire issue of the Papers of the Bibliographical Society of America, dated the same month. This 'Inquiry into Ulysses: The Corrected Text' was the next year published in book format and on floppy disk by Kidd's James Joyce Research Center at Boston University. Gabler and others rejected Kidd's critique, and the scholarly community remains divided.
Gabler edition dropped; publishers revert to 1960/61 editions
In 1990 Gabler's American publisher Random House, after consulting a committee of scholars, replaced the Gabler edition with its 1961 version, and in the United Kingdom the Bodley Head press revived its 1960 version. In both the UK and USA, Everyman's Library, too, republished the 1960 Ulysses. In 1992 Penguin dropped Gabler and reprinted the 1960 text. The Gabler version is at present available from Vintage International. Reprints of the 1922 first edition are now widely available, largely due to the expiration of the copyright for that edition in the United States.
While much ink has been spilt over the faults and theoretical underpinnings of the Gabler edition, the much vaunted Kidd edition has yet to be published. In 1992 W.W. Norton announced that a Kidd edition of Ulysses was about to be published as part of a series called "The Dublin Edition of the Works of James Joyce." This book had to be withdrawn, however, when the Joyce estate objected. The estate has refused to authorise any further editions of Joyce's work for the present, but signed a deal with Wordsworth Editions to bring out a bargain version of the novel in January 2010, ahead of copyright expiration in 2012.