If you are among those interested in the more esoteric aspects of Yeats probably already know about the International Association for the Preservation of Spiritualist and Occult Periodicals, IAPSOP, but if you don't, they have a wealth of material covering the period "between the Congress of Vienna and the start of the Second World War", so the nineteenth and early twentieth centuries.
The Archive Index features over a thousand periodical titles, most of which run to multiple issues, and includes the major journals read by W. B. and George Yeats and their "fellow students" of esoterica (AVA xii, CW13 lv). These include the spiritualist journal Light, the Theosophical journals Lucifer and the Irish Theosophist, as well as others such as the Occult Review, Borderland, the Quest, and the Astrologer's Magazine. (There are still gaps in some of the journal runs.)
Yeats himself did not publish many articles in these more specialist journals. However, in his earlier years he did contribute to Lucifer and the Irish Theosophist, for example.
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| Lucifer, 15 January 1889 (cf. Collected Works vol. IX, Early Articles and Reviews, 75ff). |
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| The Irish Theosophist, October 1892 (cf. Collected Works vol. IX, Early Articles and Reviews, 182ff). |
Most of Yeats's articles have, however, been collected and reprinted (perhaps surprisingly, not all*), and it is often the articles that were available and that he was—or could have been—reading that are of interest. These are usually unobtainable, except in the largest libraries and in many cases relatively localized, so the opportunity to find the magazines that are referred to in letters or notes and to peruse the articles being discussed is invaluable.
Seeing the intellectual influences that the Yeatses were exposed to is often illuminating and is one of the reasons why their library and marginalia are so fascinating. Yet we know that the Yeatses read these journals, and browsing almost any issue from this period can provide possible insights into the less conventional ideas they read about and provides context for their own thinking.
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| Borderland, July 1893 |
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| The Occult Review, November 1929 |
The IAPSOP site enables Search via a restricted Google search, which can be very fruitful, though recent additions may not yet be included and the vagaries of Optical Character Recognition can mean that it will not pick up all instances of the search term—a degree of lateral thinking can be useful!
The site also includes the Standard Spiritualist and Occult Corpus (SSOC) which aims "to provide, at low cost, a more or less complete document database of important primary book-length materials to all academic and non-academic researchers, aficionados, and readers interested in Spiritualism, the occult and allied parasciences" between 1790 and 1940, though with texts on either side of that declared span. It brings together material from a wide range of sources from John Dee and Le comte de Gabalis to Mathers, Lombroso, and The Scripts of Cleophas.
* One of these uncollected pieces is "A Dream of the World's End".
