Iframes in .prologue.html

[monksharru]

Hi there,
I want to embed preview of a word document using Microsoft's https://view.officeapps.live.com/op/embed.aspx?src=URL service
I have added this

<iframe src='https://view.officeapps.live.com/op/embed.aspx?src=URL.docx'</iframe>

into my .prologue.html file but it isn't rendering.
Any help would be appreciated!