Display author URL in single.php

How can I display the author website in 'single.php' template, only if the author has entered a URL in her/his profile.

I'm displaying the URL in 'author.php' but the same code doesn't work in other templates.

Th开发者_开发问答anks

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From the WP Forum: Displaying user profile's website field

<a href="<?php echo get_usermeta($post->post_author,'user_url'); ?>">HERE</a>