in mozilla, broswer ver 4.75 does not support these properties.

<STYLE TYPE="text/css">
A:visited {}
A:hover {text-decoration: underline}
A:active {}
</STYLE>

<a href="../index.htm">when hovering note that the link is underlined</a> 

A {text-decoration: none}
or
<A style="text-decoration: none" HREF="...">
will show the links without underlying. However, having links not underlined isn't a very smart idea as most people are used to having them underlined. Also, such links are not spotted unless someone coincidentally runs a mouse over them. If, for whatever reason, links without underline are required background and foreground colors can be instead declared to them so that they can be distinguished from other text, e.g.;
A {text-decoration: none; background: red; color: blue}
internal anchor link
or
<A style="text-decoration: none; background: red; color: blue" HREF="...">
Both background and foreground colors should be specified as the property that is not specified can be overridden by user's own settings.