You might be interested in the use of multibib.
This package allows you, first, to print several bibliographies in your document and, second, to use several .bib files to do so.
An example is:
\documentclass{article}
\usepackage{filecontents}
\begin{filecontents}{bibliography.bib}
@Book{Knuth:1990,
author = {Knuth, Donald E.},
title = {The {\TeX}book},
year = {1990},
isbn = {0-201-13447-0},
publisher = {Addison\,\textendash\,Wesley},
}
@Book{Lamport:94,
author = {Lamport, Leslie},
title = {{\LaTeX}: A Document Preparation System},
year = {1994},
isbn = {0-021-52983-1},
publisher = {Addison\,\textendash\,Wesley},
}
\end{filecontents}
\begin{filecontents}{bibliography_ilustration.bib}
@article{Olfati:2004,
title = {Consensus problems in networks of agents with switching topology and time-delays},
author = {Olfati-Saber, Reza and Murray, Richard M},
journal = {IEEE Transactions on automatic control},
volume = {49},
number = {9},
pages = {1520--1533},
year = {2004}
}
\end{filecontents}
\usepackage{multibib}
\newcites{secone,sectwo}{References for section 1, References for section 2}
\begin{document}
\section{Section 1}
\citesecone{Knuth:1990}
\bibliographystylesecone{unsrt}
\bibliographysecone{bibliography}{}
\section{Section 2}
\citesectwo{Olfati:2004}
\bibliographystylesectwo{unsrt}
\bibliographysectwo{bibliography_ilustration}{}
\end{document}
which gives you as a result:

However, by using multibib this way, you will have to run bibtex for each of your bibliographies:
bibtex secone
bibtex sectwo
...
This answer does the same thing using only one .bib file and several bibliography styles.
.bibfiles in one bibliography, he's asking about having two sections that each have their own bibliography. The sections shouldn't share the same bibliographie nor the same.bibfile. – Vinccool96 Apr 04 '19 at 15:07