"\Ualgocf@original@chapter" undefined when using algorithm2e with natbib

Question

Is it possible to just use plainnat without using the package natbib? When I do so, multiple author references don't work too well. I get

[author et al (year)auhtor1, author2 and author3]

when what I want is just

[author et al (year)]

Anyway to fix this?

If I add \usepackage{natbib} I just get an error:

Undefined control  sequence.

\chtapter ...ace {10\p@ }}\algocf@original@chapter

1.1 \begin{thebibliography}{28}

So using plainnat without natbib is the closest I got to get this working.

Example:

\documentclass[a4paper,12pt]{article}
\usepackage{amsmath}
\usepackage{amsfonts}
\usepackage{amssymb}
\usepackage{graphicx}
\usepackage{rotating}
\usepackage{listings}
\usepackage[ruled,vlined]{algorithm2e}
\usepackage[ngerman,english]{babel}
\usepackage{babelbib,url} 
\usepackage{breakcites}
%\usepackage{natbib}
%\usepackage[square, comma, sort&compress]{natbib}
\usepackage[latin1]{inputenc}
\usepackage{pslatex}
\usepackage{setspace}
\setstretch{2} 
\begin{document}
    \cite{DPS2000}
\newpage\pagebreak
\nocite{*}
\bibliographystyle{plainnat}
\bibliography{references}
\end{document}

It compiles fine but I get

[author et al (year)auhtor1, author2 and author3]

style referencing and if I uncomment natbib it won't compile.

Answer 1

The problem is that the algorithm2e expects \chapter to be defined. It makes some changes to how the bibliography is printed which do not make sense. One fix is to do

\let\chapter\section

before loading algorithm2e: the problem should be go away.

Answer 2

Load algorithm2e after natbib.