Adding more items on tex article title section

Question

This is what I have at the head of my tex document (article):

\title{Some Article}
\author{John Doe}

\date{\today}

\documentclass[pdftex,12pt,a4paper]{article}
\usepackage{setspace}
\usepackage[textwidth=16cm,textheight=24cm]{geometry}
\begin{document}
\maketitle
. . .

I want to add a subtext below the title. As shown in the practical example given here I want to have the author's name on the left side, and supervisor's name on the right side. How can I do it? I tried the example from the above link, but, while compiling, it shows the error: document begin is not specified.

Answer 1

You can create your own title page using the titlepage environment (as shown by the linked page you posted). One important thing to note is that it replaces the \maketitle command, i.e. it has to be placed after the \begin{document} not before. I think this is your problem.

Also for articles you would need to disable the page break at the end of the titlepage environment (See also Preventing page break after title page).

Here some working example:

\documentclass[12pt,a4paper]{article}
\usepackage{setspace}
\usepackage[textwidth=16cm,textheight=24cm]{geometry}

\begin{document}
\begin{titlepage}
    \begin{center}
        \vspace*{5cm}%
        {\huge The Title}\\[1cm]
        {\Large The SubTitle}\\[1cm]
        %...
    \end{center}
    \let\newpage\relax% Avoid following page break
\end{titlepage}

\end{document}