Scusate, nel tentativo di evidenziare in grassetto le parole titlesec e fancyhdr all’interno del codice ho fatto un pasticcio.
Ripropongo il codice ripulito:
`
\documentclass[12pt,a4paper,openright,twoside,italian,titlepage,tight]{book}
\usepackage{lipsum}
\usepackage[italian]{babel}
\usepackage[a4paper,top=3.5cm,bottom=3.5cm,left=4cm,right=4cm,bindingoffset=1cm,heightrounded]{geometry}
\usepackage[utf8x]{inputenc}
\usepackage{setspace}
\onehalfspacing
\usepackage{indentfirst}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage[tiny]{titlesec}
\titleformat*{\subsection}{\itshape}
\titleformat{\chapter}[display]{\center\bf\LARGE}{\MakeUppercase\chaptertitlename\ \thechapter}{20pt}{\Large\sc\MakeUppercase}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\usepackage{fancyhdr}
\fancyhf{}
\renewcommand{\headrulewidth}{0.5pt}
\renewcommand{\footrulewidth}{0pt}
\setlength{\headheight}{14.5pt}
\fancyfoot[C]{\bfseries\thepage}
\fancyhead[LO]{\footnotesize\bfseries\nouppercase{\rightmark}}
\fancyhead[RE]{\footnotesize\bfseries\nouppercase{\leftmark}}
\pagestyle{fancy}
\renewcommand{\chaptermark}[1]{\markboth{#1}{}}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\addto\captionsitalian{%
\renewcommand{\contentsname}{Indice Sommario}%
}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\begin{document}
\frontmatter
\tableofcontents
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\chapter{Presentazione}
\lipsum
\mainmatter
\chapter{Titolo capitolo uno}
\lipsum
\chapter{Titolo capitolo due}
\lipsum
\chapter{Titolo capitolo tre}
\lipsum
\end{document}
`
Grazie ancora