Apostrophe ending a word sticks to next word

The title of a work I have to cite has a word ending with an apostrophe. Given this post, I'm using the ASCII single quote (') to write the entry, but this generates the following problem:

As you can see, the words "managers'" and "prior" are stuck. I checked how this article is cited on Google Scholars. To my surprise, they use the Unicode "right single quotation mark" (’). I used it in my .bib file and it worked!

Why does this happen?

@article{sandor01_conjoint,
title   = "Designing conjoint choice experiments using managers' prior beliefs",
author  = "Zsolt Sándor and Michel Wedel",
year    = "2001",
journal = "Journal of Marketing Research",
volume  = "38",
number  = "4",
pages   = "430--444"
}

@article{sandor01_conjoint,
title   = "Designing conjoint choice experiments using managers’ prior beliefs",
author  = "Zsolt Sándor and Michel Wedel",
year    = "2001",
journal = "Journal of Marketing Research",
volume  = "38",
number  = "4",
pages   = "430--444"
}


Edit: I add a MWE. The packages that fix the language to spanish are mandaroty, because the references have to be in spanish (e.g. Name Surname y Name Surname instead of Name Surname and Name Surname).

\documentclass[letterpaper, 12pt, oneside]{book}

\usepackage[activeacute,spanish]{babel}
\usepackage[utf8]{inputenc}

\usepackage[fixlanguage]{babelbib}
\selectbiblanguage{spanish}

\begin{document}

Hello world \cite{sandor01_conjoint}

\bibliographystyle{babalpha-fl}
\bibliography{bibliografia}

\end{document}

• Can you please add a minimal example of LaTeX code? – egreg Dec 26 '16 at 15:20
• Please add a minimal working example (MWE) that illustrates your problem. Currently nobody can reproduce your output without a lot of effort. – Henri Menke Dec 26 '16 at 15:20

Remove the activeacute option: if you use UTF-8 you don't need it.

\begin{filecontents*}{\jobname.bib}
@article{test1,
title   = "Designing conjoint choice experiments using managers' prior beliefs",
author  = "Zsolt Sándor and Michel Wedel",
year    = "2001",
journal = "Journal of Marketing Research",
volume  = "38",
number  = "4",
pages   = "430--444"
}

@article{test2,
title   = "Designing conjoint choice experiments using managers’ prior beliefs",
author  = "Zsolt Sándor and Michel Wedel",
year    = "2001",
journal = "Journal of Marketing Research",
volume  = "38",
number  = "4",
pages   = "430--444"
}
\end{filecontents*}

\documentclass[letterpaper, 12pt, oneside]{book}

\usepackage[spanish]{babel}
\usepackage[utf8]{inputenc}

\usepackage[fixlanguage]{babelbib}
\selectbiblanguage{spanish}

\begin{document}

Hello world \cite{test1} and \cite{test2}

\bibliographystyle{babalpha-fl}
\bibliography{\jobname}

\end{document}


The filecontents* environment is used just to make the example self-contained and not clobber my files.

If you really need activeacute, type in the apostrophe as

Designing conjoint choice experiments using managers'{} prior beliefs

• Whoa! I never thought activeacute could cause this issue. As I understand, the option allows me to write accents using the \'a format to obtain á. Now that I think about it, given that I use \usepackage[utf8]{inputenc}, activeacute is no longer necessary. – Ignacio Correa Dec 26 '16 at 17:47
• @IgnacioCorrea The option allows you to type 'a (without backslash) to get á. You can still type \'a without the option, if you prefer. – egreg Dec 26 '16 at 17:50
• You're right, but as a native spanish speaker, it is much more comfortable to type á right away than 'a or \'a, because of grammar checks and the like. Thank you for your answer and comment! – Ignacio Correa Dec 27 '16 at 17:43

Various things like managers{'} prior did not work, but managers'\ prior did work.

\documentclass[letterpaper, 12pt, oneside]{book}

\usepackage[activeacute,spanish]{babel}
\usepackage[utf8]{inputenc}

\usepackage[fixlanguage]{babelbib}
\selectbiblanguage{spanish}
\usepackage{filecontents}
\begin{filecontents*}{bibliografia.bib}
@article{sandor01_conjoint,
title   = "Designing conjoint choice experiments using managers'\ prior beliefs",
author  = "Zsolt Sándor and Michel Wedel",
year    = "2001",
journal = "Journal of Marketing Research",
volume  = "38",
number  = "4",
pages   = "430--444"
}
\end{filecontents*}

\begin{document}

Hello world \cite{sandor01_conjoint}

\bibliographystyle{babalpha-fl}
\bibliography{bibliografia}

\end{document}