Using the API graph I only get the likes of the publications, but many times they are not the total number of likes of the publication, since the likes that are received as ad don't include them.
Here is the call to the API graph:
https://graph.facebook.com/v2.10/".$this->id_bussiness_account."?fields=business_discovery.username(".$id_count."){id,biography,followers_count,website,username,media_count,media{id,caption,comments_count,like_count,media_url,media_type,timestamp,permalink}}"