Problem with multiple languages in BibTeX

Question

I'm new here. I'm typing my Thesis and I'm using two languages (Spanish, English). This is my code:

\documentclass[hidelinks,letterpaper,titlepage,12pt,oneside,spanish,final]{report_eie}
\usepackage[english,spanish]{babel} 
\usepackage[latin1]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amssymb}
.
.
\usepackage{indentfirst} %(Because I have declared a new language, english)
\usepackage[apaciteclassic]{apacite}
\usepackage[round,authoryear]{natbib}
.
.
\begin{document}
\selectlanguage{spanish} 
.
.
.
\bibliographystyle{apacite}
\renewcommand{\bibname}{REFERENCIAS}
\let\oldbibsection\bibsection
\bibliography{biblioteca} 
.
.
.
\end{document}

All works but the bibliography is showed in English (for example, the ordinal numbers are showed "Nth", instead of Nª, "and" instead of "y", etc). If I type \usepackage[spanish]{babel} and delete \selectlanguage{spanish} the bibliography is showed in Spanish. What I can do? I need to use both languages.

Answer 1

If I understand you correctly, you want Spanish entries in the bibliography to be handled like they should be in Spanish, and English entries similarly in English?

If this is the case, You'll have to use a bibtex style that is capable of switching the language for each entry in the bibliography.

biblatex package provides such a functionality, by using an additional field 'hyphenation' langid for each bibtex database entry. This field indicates the language the entry should be presented in, thus allowing biblatex to put each entry in a correct babel language environment. Then you'll get each entry in the bibliography to behave its correctly.