\documentclass{book}
\usepackage{amsfonts}
\usepackage{amsmath}
\usepackage[gen]{eurosym}
\usepackage{textcomp}
\usepackage{graphicx}
\usepackage{etoolbox}
\usepackage{titleps}
\usepackage[ISO-8859-1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{imakeidx}
\usepackage{float}
% use hidelinks to remove boxes around links to be similar to Texinfo TeX
\usepackage[hidelinks]{hyperref}

\makeatletter
\newcommand{\Texinfothechapterheading}{}
\newtitlemark{\Texinfothechapterheading}%
\newcommand{\Texinfoheadingchaptername}{\chaptername}
\newtitlemark{\Texinfoheadingchaptername}%
\newcommand{\Texinfosettitle}{No Title}%

\newcommand{\Texinfounnumberedchapter}[1]{\chapter*{#1}
\addcontentsline{toc}{chapter}{\protect\textbf{#1}}%
\renewcommand{\Texinfothechapterheading}{}%
\chaptermark{#1}%
}%

\newcommand{\Texinfounnumberedpart}[1]{\part*{#1}
\addcontentsline{toc}{part}{\protect\textbf{#1}}%
}%

\newcommand{\Texinfounnumberedsection}[1]{\section*{#1}
\addcontentsline{toc}{section}{\protect\textbf{#1}}%
\sectionmark{#1}%
}%

\newcommand{\Texinfounnumberedsubsection}[1]{\subsection*{#1}
\addcontentsline{toc}{subsection}{\protect\textbf{#1}}%
}%

\newcommand{\Texinfounnumberedsubsubsection}[1]{\subsubsection*{#1}
\addcontentsline{toc}{subsubsection}{\protect\textbf{#1}}%
}%

\newcommand{\Texinfochapter}[1]{\chapter{#1}
\renewcommand{\Texinfothechapterheading}{\Texinfoheadingchaptername{} \thechapter{} }%
}%

% no index headers
\indexsetup{level=\relax,toclevel=section}%
\makeindex[name=cp,title=]%

% redefine the \mainmatter command such that it does not clear page
% as if in double page
\renewcommand\mainmatter{\clearpage\@mainmattertrue\pagenumbering{arabic}}
\newenvironment{Texinfopreformatted}{%
  \par\GNUTobeylines\obeyspaces\frenchspacing\parskip=\z@\parindent=\z@}{}
{\catcode`\^^M=13 \gdef\GNUTobeylines{\catcode`\^^M=13 \def^^M{\null\par}}}
\newenvironment{Texinfoindented}{\begin{list}{}{}\item\relax}{\end{list}}

% used for substitutions in commands
\newcommand{\Texinfoplaceholder}[1]{}

\newpagestyle{single}{\sethead[\Texinfothechapterheading{}\chaptertitle{}][][\thepage]
                              {\Texinfothechapterheading{}\chaptertitle{}}{}{\thepage}}

% allow line breaking at underscore
\let\Texinfounderscore\_
\renewcommand{\_}{\Texinfounderscore\discretionary{}{}{}}
\renewcommand{\includegraphics}[1]{\fbox{FIG \detokenize{#1}}}

\makeatother
% set default for @setchapternewpage
\makeatletter
\patchcmd{\chapter}{\if@openright\cleardoublepage\else\clearpage\fi}{\Texinfoplaceholder{setchapternewpage placeholder}\clearpage}{}{}
\makeatother
\pagestyle{single}%


\begin{document}
\label{anchor:Top}%
\Texinfochapter{{ä ë ï ö ü ÿ Ä Ë Ï Ö Ü}}
\label{anchor:_00e4-_00eb-_00ef-_00f6-_00fc-_00ff-_00c4-_00cb-_00cf-_00d6-_00dc}%

\Texinfochapter{{é}}
\label{anchor:_00e9}%

\Texinfochapter{{à è ù}}
\label{anchor:_00e0-_00e8-_00f9}%

\Texinfochapter{{â ê î ô û Â Ê Î Ô Û}}
\label{anchor:_00e2-_00ea-_00ee-_00f4-_00fb-_00c2-_00ca-_00ce-_00d4-_00db}%

\Texinfochapter{{ç}}
\label{anchor:_00e7}%

\hyperref[anchor:_00e4-_00eb-_00ef-_00f6-_00fc-_00ff-_00c4-_00cb-_00cf-_00d6-_00dc]{\chaptername~\ref*{anchor:_00e4-_00eb-_00ef-_00f6-_00fc-_00ff-_00c4-_00cb-_00cf-_00d6-_00dc} [ä ë ï ö ü ÿ Ä Ë Ï Ö Ü], page~\pageref*{anchor:_00e4-_00eb-_00ef-_00f6-_00fc-_00ff-_00c4-_00cb-_00cf-_00d6-_00dc}}
\hyperref[anchor:_00e9]{\chaptername~\ref*{anchor:_00e9} [é], page~\pageref*{anchor:_00e9}}
\hyperref[anchor:_00e0-_00e8-_00f9]{\chaptername~\ref*{anchor:_00e0-_00e8-_00f9} [à è ù], page~\pageref*{anchor:_00e0-_00e8-_00f9}}
\hyperref[anchor:_00e2-_00ea-_00ee-_00f4-_00fb-_00c2-_00ca-_00ce-_00d4-_00db]{\chaptername~\ref*{anchor:_00e2-_00ea-_00ee-_00f4-_00fb-_00c2-_00ca-_00ce-_00d4-_00db} [â ê î ô û Â Ê Î Ô Û], page~\pageref*{anchor:_00e2-_00ea-_00ee-_00f4-_00fb-_00c2-_00ca-_00ce-_00d4-_00db}}
\hyperref[anchor:_00e7]{\chaptername~\ref*{anchor:_00e7} [ç], page~\pageref*{anchor:_00e7}}

\index[cp]{ä ë ï ö ü ÿ@ä ë ï ö ü ÿ}%
\index[cp]{Ä Ë Ï Ö Ü@Ä Ë Ï Ö Ü}%
\index[cp]{é@é}%
\index[cp]{è@è}%
\index[cp]{â ê î ô û Â Ê Î Ô Û@â ê î ô û Â Ê Î Ô Û}%
\index[cp]{ç@ç}%

\end{document}
