How do I add the nofollow attribute to the deeplinks calls?

nofollow is a value that can be assigned to the rel attribute of an HTML a element to instruct some search engines that a hyperlink should not influence the link target's ranking in the search engine's index. You should add the attribute rel="nofollow" to the anchor elements pointing to the deeplinks, for example:

<a href="/deeplink here/" rel="nofollow">book flight</a>

Please have a look at the following links in order to get more information:
http://en.wikipedia.org/wiki/Nofollow
https://support.google.com/webmasters/answer/96569?hl=en
http://google.about.com/od/searchengineoptimization/qt/how_to_make_nofollow_tag.htm