% !TEX TS-program = pdflatex
% !TEX encoding = UTF-8 
% !TEX spellcheck = fr_FR
\documentclass[a4paper,11pt]{report}
\usepackage[utf8]{inputenc}
\usepackage[french]{babel}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{etoolbox}
\usepackage[left=25mm,right=20mm,top=20mm,bottom=20mm,ignoreheadfoot]{geometry}
\usepackage{csquotes}
\usepackage[backend=biber,style=authoryear-comp]{biblatex}
\ExecuteBibliographyOptions{sortcites, sortlocale=auto, sorting=nyt, maxnames=3, minnames=3, backref, date=year, language=auto, texencoding= utf8, bibencoding=utf8}
\usepackage{hyperref}
%%===========================================
\newcommand{\multibib}[1]{
	\providebool{bibfirst}
	\forcsvlist{\listxadd\multibiblist}{#1}
	\DeclareListParser*{\myforbibitem}{=}
	\expandafter\renewcommand{\do}[1]{
		\booltrue{bibfirst}
		\myforbibitem{\ifbool{bibfirst}{\boolfalse{bibfirst}\xdef\mybibkeyword}{\xdef\mybibfile}}{##1}
	 	\map{\perdatasource{\mybibfile}\step[fieldset=keywords, fieldvalue=\mybibkeyword,append]}
	 }
	 \DeclareSourcemap{\maps[datatype=bibtex]{%
	 \dolistloop{\multibiblist}
	 }}
}
%%===========================================

\addbibresource{snom.bib}
\addbibresource{tori.bib}
\multibib{primaire=tori.bib,secondaire=snom.bib}

%----------------------------------
\begin{document}
%----------------------------------
\chapter{premier chapitre}


Une citation \autocite{BetzigTrautman91}\par
\bigskip


\nocite{*}

\cleardoublepage

%\printbibliography
\printbibheading
\printbibliography[keyword=primaire, heading=subbibliography,title=SNOM]
\printbibliography[keyword=secondaire, heading=subbibliography, title=Tori]

%----------------------------------
\end{document}
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%

