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Hi Fabrizio, I'd advise you to link to your regular (non AMP) page. Make sure that this page includes a tag with a link to the AMP version of the page. The AMP page should then contain a rel canonical tag to the non AMP version. Because of this canonical tag it makes more sense to focus your link building efforts on the non AMP version of the page. See https://www.ampproject.org/docs/fundamentals/discovery for more detailed information on how to include the tags on both pages. Hope it helps!