No one writes after they die. This simple fact is the foundation of the so-called “historical layering principle”, which requires SSA authors to bear this fact in mind, and expressly take account of this fact in finalizing their writing for publication. That no one writes after death is the factual summary of historical layering as a principle of reference style, and the SSA Style Sheet is so far the only style sheet that takes this universal fact into explicit account.* The uniqueness of SSA Style for publications, then, is simply the requirement that authors citing sources take not only scholarly but also temporal account of the “historical layers” implicit in their use of others’ writings.
Thus, in SSA writings, both ideally and as a matter of principle the reference or “source” date for a work in relation to its author should normally be taken from within the lifetime of that author or “source”. Other dates may be important in the particular case, as when the work is a translation or a particular edition—the “access volume”. If the access volume is an edition from outside the source’s lifetime, or a translation, that information—the access date for the work—will be given in the final list of References; but in every case the reference year is that of the source work. The complete “References” list, at the end of the article, otherwise follows standard form, arranged alphabetically by last name of authors; for SSA, note that all last names are to be placed in capital letters.
This distinction between “source works”, tied to the lifetime of the text’s author, and “access volumes”, which may or may not be the same as the source work, in sum, is the basis for the principal distinctive feature of SSA Style, namely, the historical layering of sources. This principle of historical layering on which the SSA Style Sheet rests was adopted for its simplicity compatible with the informational content demanded by all existing reference styles, but with this improvement: when fully implemented, the SSA Style uniquely establishes for any given work cited an invariant reference base across all the disciplines, in accord with the inherently interdisciplinary nature of semiotics itself.
References historically layered enable the reader to see at a glance the time dimension of the discourse, much as a geologist is able to see in the layers of rock the history of the earth. In general, manuscript submissions are expected to be submitted conscientiously prepared in accord with the historical layering principle, and to be complete as far as the scholarly intent and state of the knowledge of a field allows. The full version of the Style Sheet is available in The America Journal of Semiotics 4.3–4 (1986), 193–215, and in the Semiotics 1984 Proceedings volume pp. 715–739. An abbreviated version is provided here.
A second unique feature of SSA Style concerns punctuation placement. Respecting the purpose of quotation marks, which is to show what was actually said or written, the rule for punctuation is: punctuation which belongs to the source cited belongs inside quotation marks; otherwise punctuation belongs after the closing of the quotation marks. (Thus, the SSA Style Sheet opts for logic over custom, by eschewing the standard but arbitrary American practice of putting all punctuation marks inside of quotation marks.) Please note this well, for, as Peirce best called to our attention, logic is required for thought to be disciplined, especially in matters where an arbitrary bad habit of ignoring logic has taken root.
* The SSA Style Sheet has been adopted by the University of St. Thomas Center for Thomistic Studies for its publications program and also for the preparation of undergraduate papers, graduate papers, and dissertations: see their PDF.