\documentclass{}
\usepackage{amssymb, amsmath, hyperref}
\usepackage{preamble}

\begin{document}

Hi, welcome to my digital garden, where I collect math results that I learn. 

Despite the contents being presented in a linear order by the table of contents, I will frequently reference things between chapters and sections. 

Occasionally, I make up some definitions to play with. These definition blocks will always have a * at the end of its title to indicate that it lives mostly in my head. These terms will always be referenced with a link to their definition block. 

\input{./src/cat/index}
\input{./src/topology/index}
\input{./src/fa/index}
\input{./src/measure/index}
\input{./src/dg/index}
\input{./src/op/index}
%\input{./src/process/index}

\bibliographystyle{alpha} % We choose the "plain" reference style
\bibliography{refs.bib} % Entries are in the refs.bib file

\end{document}