Reference webservice on a regular html page not ASPX

I was working with this example ?How Do I: Make Client-Side Network Callbacks with ASP.NET AJAX?? on the videos section at: http://www.asp.net/learn/ajax-videos/video-79.aspx

But what I?m trying to do is the same thing but instead of ASPX page in a regular HTML page.

Is this possible?

Thank you

 
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