[Plugin: Advanced Custom Fields] ACF Creating a "Read More" field with URL

Any coders out there who can possibly show me how to create a field using Advanced Custom Fields plugin, where I enter a url, and then The text Label would be “Read More” and when clicked, goes to the specified URL?

Basically, I’d like to cite news articles in my blog,
RAther than copying a paragraph for each article, and then Typing Read More and linking each “read more” to the relevant URL, i’d just like to paste the URL in a custom field and then automatically a Read more label is created

I would imagine i’m supposed to use the Page Link field, but this only seems to link to internal articles, How do i link to an external URL?

Any help would be so appreciated , thank you

http://wordpress.org/extend/plugins/advanced-custom-fields/