<html><head><style type="text/css"><!-- DIV {margin:0px;} --></style></head><body><div style="font-family:times new roman, new york, times, serif;font-size:18pt"><DIV>Hi </DIV>
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<DIV>I am a new user to the Tex system. I wrote my thesis using havard package refrence style, but now I want to use natbib package. So I put \usepackage{natbib}, used <A href="file://\\bibliographystyle{plainnat">\bibliographystyle{plainnat</A>} and also changed cite to \citet{}. But don't know why I am getting this following error message. </DIV>
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<DIV><FONT color=#ff0000>! undefined control sequence</FONT></DIV>
<DIV><FONT color=#ff0000>1.5 \havartcite</FONT></DIV>
<DIV><FONT color=#ff0000> {chaudhry08}{}{}{}</FONT></DIV>
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<DIV><FONT color=#000000>I thought that it would be simple. Now I don't have any idea what's I am doing wrong. Any help would be appreciable.</FONT></DIV>
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<DIV>Thanks.</DIV>
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<DIV>Mostafa</DIV>
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