For reference, the Information for Authors page of Theory and Applications of categories follows. It has been updated with assistance from Michael Barr. The TAC style (tac.sty) and class (tac.cls) files have also been updated, so please replace any copies you may have. AUTHOR INFORMATION Theory and Applications of Categories (TAC) is an all-electronic journal which uses the TeX typesetting system to define its contents and the Internet to disseminate them. Authors are invited to submit articles to any member of the Editorial Board. While any standard flavour of TeX (i.e. plain, LaTeX, AMS-(La)Tex) may be submitted, the most important request to an author of a TAC paper is to use one or another version of LaTeX. This encourages the logical formatting that is described below. Before submitting an article please read about the Format for submission . All papers are refereed and acceptance of an article by an Editor indicates that the high standards of the journal have been met. Articles may be submitted to only one member of the Board. The final accepted version of a paper is the form that will be in the archive; the author will not be able to make any changes, except: errata and additions can be attached to the end and, where appropriate, footnote(s) may be added to the main text calling attention to these addendums; references which mention pre-publication versions may be updated to final bibliographic form. Accepted papers will be archived electronically in .dvi and Postscript format by the journal. In addition, there are several complete mirrors of the journal's contents on the Internet. A printed paper copy of each article in the journal is archived in the Mount Allison University Library. Authors retain ownership of copyright to their work, subject to appropriate use of the work by the journal. For details consult the Copyright Agreement, to which authors must agree before an accepted paper is published. FORMAT FOR SUBMISSION: SOURCE FILES TeX source files of articles may be submitted by email to any member of the Editorial Board. Editors may also provide facilities for receiving articles by file transfer. Editors will not correct errors in TeX source. It is the author's responsibility to provide a compilable source file. The source file for an article must begin with a comment which includes the following information: the flavour of TeX used, the number of pages, any diagram macro package used, any non-standard fonts, the implementation of TeX used in preparation of the article. An example might be % LaTeX 2.09 document, 12 pp, XY-pic ver 3.1, emTeX version 3.1 An article is normally submitted as a single source file. All macros must be included with the source file and are the responsibility of the author. Macros should be placed at the beginning of the file. It is also helpful if any macro that is not actually used is deleted from the source file. The only exception to inclusion of macros is diagram macro packages. The currently acceptable diagram macro packages are those authored by Barr, Borceux, Rose (XY-Pic) and Taylor. The author is responsible to ensure that the current version of a macro package has been used. Articles must include an Abstract, in English of not more than 200 words. AMS 2000 Subject Classification must also be also be included. SOURCE FILE STYLE As indicated above LaTeX is the preferred format. Using LaTeX will facilitate consideration of an article, but papers in other standard TeX flavors will be considered. A style file is available from the journal. Using the style file during preparation of articles will greatly reduce the acceptance to publication delay. Whether or not the journal's style is used, the most important advice for an author of TAC (or any electronic journal or even any journal that accepts TeXscripts) is to use logical, rather than physical formatting. That is, instead of beginning a section by saying \medskip \noindent{\bf 4.3 The main theorem.} just say \section{The main theorem}\label{mainth} (The \label will be explained below.) Instead of saying \smallskip \noindent{\sc Theorem A}{\it ...} say \begin{theorem}\label{thmA} ... \end{theorem} (shorter forms as will be explained later). You should probably NEVER put explicit skips and kerns into your paper. Suppose, for example, you want to go on to a new topic and want to leave a little space. The preferable way is to say \subsubsection*{} which will have exactly that effect. But in fact, it is probably always appropriate to start a new subsection in such a case. Except in very long papers, we discourage the use of three indexing levels. The point is to use symbolic formatting and let the journals put in their own style. All versions of LaTeX provide definitions for \section, \subsection, and \subsubsection. It even goes further, but these should be enough for nearly all papers. They do not provide definitions for \begin{theorem} and the like. But the TAC style files provide a \newtheorem macro that is used as follows. Place at the beginning of your paper, the following: \newtheorem{theorem}{Theorem} \newtheorem{proposition}{Proposition} ... (whatever is needed) The first parameter is what you will call it in your TeXscript and the second what it will be called in your paper. So you can just as well say \newtheorem{thm}{Theorem} ... and then you can enclose your theorems in \begin{thm}...\end{thm} or even \thm...\endthm. Beware that you lose certain error checking with the latter form. AVOIDABLE ERRORS There are two mistakes made by many users of TeX that appear in print over and over and are easy to avoid. The first is to have multicharacter identifiers slanted (like math symbols), rather than in upright type. This refers to names like sin, cos,... but also Hom, Tor, Id, ker, Im, .... The TAC style files provide macros that can automate this. If you put in your file \mathrmdef{Hom} this will create a macro \Hom that will put upright Hom into your text. If you use that instead of just Hom, the results will look much better. Using just Hom in math mode will result in an italic font and ugly spacing that is more appropriate to a ternary product. TAC also supplies \mathbfdef (for bold), and \mathopdef (for upright characters that have a bit of extra space to the right, so that, say, \sin x will produce the sin, a small space and then an italic x, just as in the trig books). The second error is to use <...> for angle brackets. You have no idea how bad this will look. The < and > produce the wrong shape for angle brackets, but mainly they produce the wrong spacing and the results can be ludicrous, especially if an = follows > or precedes <. The official way to do this is to say \langle and \rangle. Many papers in TAC use these angle brackets extensively and make little or no use of the inequality signs. If this is your case, we recommend the following. At the top of your paper, put: \mathcode`\<="4268 %left delimiter \mathcode`\>="5269 %right delimiter \mathchardef\gt="313E %relation \mathchardef\lt="313C %relation The effect of the first two lines is to make < and > into \langle and \rangle, respectively, so that you can use them freely. The third and fourth lines allow you to use \lt and \gt for the inequality signs. This is not done in the TAC styles because an author has the right to use < and
for the inequalites if desired.
Fonts Authors should note that the base font size is 12 point. Avoid use of elements which depend on another base font size. This is another reason to avoid absolute moves such as `\vskip 10 pt'. Remember that the journal's pagination will differ from yours. As a general rule less, but more logical, formatting is better. Authors are STRONGLY encouraged to use only fonts from the standard TeX distribution (cmr etc.), AMS symbol fonts (msym...) or the XY-pic fonts. They should be aware that use of non-standard fonts can interfere with successful dissemination of their work. Fonts not mentioned above must be provided by the author to the Editor concerned and to the journal. Embedded graphics or Postscript are not currently accepted. REFERENCES AND BIBLIOGRAPHY STYLES When you want to refer to Theorem A (which will not be called that in the TAC style) of Section 4.3, refer to it as Theorem~\ref{thmA} of Section~\ref{mainth}. The labels you use are totally arbitrary, of course, so long as they are not reused in the same paper. Use of symbolic labels allows you to insert or delete material without having to renumber everything or to wind up with sections or theorems bis. The ~, by the way, is an unbreakable space so that the theorem or section number does not get separated from the word Theorem or Section. This is considered poor style, although it is not terribly important. It is also an element of good style to capitalize the words Section and Theorem when followed by an explicit reference. However, they are not capitalized in such phrases as "next section" and "the main theorem". If BiBTeX is used with LaTeX, bibliographies must be BiBTeXed and .bbl files appended to the source file. No .bib files will be accepted. References may use the standard BiBTeX styles or the two bibliography styles that TAC supports. We recommend the first TAC style. It is much more useful for the reader since it puts citations like [Grothendieck, 1957] in your text (you can probably already guess the reference) and the reference in the form \item A. Grothendieck (1957), Quelques points d'algebre homologiques, T\^ohoku Math. J. \em{3}, 120-221. You get the first style by preceding your references with \begin{references} and ending the list of \items with \end{references} The second style is traditional and puts [4] into your paper with the reference in the traditional form \item A. Grothendieck, Quelques points d'algebre homologiques, T\^ohoku Math. J. \em{3} (1957), 120-221. To obtain it use \begin{references*} \item ... \end{references*} except you will almost surely want to use \bibitem, allowing you to put in a symbolic label. A FINAL POINT Although these instructions are specific to TAC, they should go a long way towards making your papers usable by any journal that is serious about using author-supplied TeX.