I want to citing the numeric references using BibTeX. Problem arise when I try to cite a reference at the beginning of a sentence. e.g., when I try to cite \citet{TrHe02} at the beginning of sentence the I got "(author?)[1]". Actually the citation should be "Trampert and Heijst [1]". But when I cite the same at end or inbetween the sentence using "citep" or "cite" then I got citation correctly as "[1]". How to get the correct citation as "Trampert and Heijst [1]" at he beginning of sentence?. Below I have given my latex script with content of reference file and file which i have used inside script with the link.
\documentclass[preprint,12pt]{elsarticle}
\begin{document}
\section{Introduction}
\citet{TrHe02}, when I use "citet" then i get the problem, but if cite it as ''citep'' or ''cite'' then i just got the numeric reference.
\cite{TrHe02}, here i used just use cite at the beginning i just got the numeric reference as [1]. Actually i should get as Trampert and Heijst \citep{TrHe02}. I have manually written Trampert and Heijst.
From here details of the file which i have use while running the script.
In the latex script all this file elsarticle and elasrticle-num are standard which i have taken from website. This is the link
\verb+http://www.elsevier.com/author-schemas/the-elsarticle-latex-document-class+
And the file to be download is elsarticle.zip
I am using elsarticle-template-num.tex, elsarticle-num.bst and
elsarticle.cls
\bibliographystyle{elsarticle-num}
\bibliography{refs}
\end{document}
% refs.bib is my reference file and it contain
@STRING{SCI={Science}}
@article{TrHe02,
AUTHOR ={Trampert, J. and Heijst, H. J. V.},
TITLE ={Global Azimuthal Anisotropy in the Transition Zone},
YEAR ={2002},
JOURNAL =SCI,
VOLUME={296},
NUMBER={},
MONTH ={},
PAGES ={1297-1299}
}