Taking off the reference number from in text cite

Question

I have a question about how to take off the reference number from in text cite? to explain more, I am using a thesis template, which uses the bibtex. This is how I cite a reference in text:

\citep[Rost and Riebesell, 2004]{rost2004coccolithophores}

the previous line produce a number before the Author names as follow: ....(1, Rost and Riebesell, 2004) and when I use additional square brackets the number appears to the right of the names:

\citep[Rost and Riebesell, 2004][]{rost2004coccolithophores}

the cite will appear as follow:

....(Rost and Riebesell, 2004 1)

I want to take off this number from the in text cite to be like this:

....(Rost and Riebesell, 2004)

So I hope someone will guide me to the right way to do this?

here is the reference that I included in a file "thesis.bib":

@article{rost2004coccolithophores,
title={Coccolithophores and the biological pump: responses to environmental changes},
author={Rost, Bj{\"o}rn and Riebesell, Ulf},
booktitle={Coccolithophores},
pages={99--125},
year={2004},
publisher={Springer}
}

and I used the same package of \usepackage{natbib}, \bibliographystyle{apalike} and \bibliography{thesis}, but when I run the file I got this message:

Package natbib Error: Bibliography not compatible with author-year citations. ...mand\NAT@force@numbers{}\NAT@force@numbers

Answer 1

Given the nature of the bibliographic entry in question, I suggest changing its type from @article to @incollection. One shouldn't use the @article entry type for pieces that weren't published in journals. I would also insert fields called editor and address and augment the booktitle field.

With these modifications in place, and with the natbib package loaded and the bibliography style set to apalike, the following output is generated by \citep{rost2004coccolithophores}. If you encounter any errors, try deleting all aux files and recompiling from scratch (LaTeX, BibTeX, and LaTeX twice more).

\documentclass{article}
\usepackage{filecontents}
\begin{filecontents*}{thesis.bib}
@incollection{rost2004coccolithophores,
  author = "Bj{\"o}rn Rost and Ulf Riebesell",
  title  = "Coccolithophores and the biological pump: responses to environmental changes",
  pages  = "99-125",
  editor = "Hans A. Thierstein and Jeremy R. Young",
  booktitle = "Coccolithophores: From Molecular Processes to Global Impact",
  publisher = "Springer",
  address   = "Berlin",
  year   = 2004,
}
\end{filecontents*}

\usepackage{natbib}
\bibliographystyle{apalike}

\begin{document}
\citep{rost2004coccolithophores}
\bibliography{thesis}
\end{document}