I have been looking for THE manual for using class 'article' in LaTex. The official CTAN package site points to some documentation which actually is 'an introduction to writing classes and packages for LATEX'; it does not cover how to use the article package.
I need to, for instance, check what is the command for inserting affiliations, or to place in-text references, among other typical tasks you will do while preparing a scientific paper. I would like to have the official way to do that at hand. Looking in Google for those commands returns disparate solutions relying on additional packages. And that is something I must avoid because of editorial regulations.
Can you please provide the link to a standard manual?

articledocument class, and you will thus not find it in a discussion of what this document class does or does not do. For some of the introductory-level material, I suggest you study carefully the document The Not So Short Introduction to LaTeX2e by Oetiker et al. – Mico Sep 13 '14 at 18:58\authormacro. In practice, the issue of just how to display authors' affiliations comes up most urgently when you're submitting a paper to a journal. Fortunately, most journals that accept LaTeX input provide specialized document classes (e.g, elsarticle for Elsevier-affiliated journals) that provide their own syntax for listing authors and affiliations. This removes all the guesswork (and creativity!) out of the question of how to display those pesky affiliations... – Mico Sep 13 '14 at 19:39