Gaining citations is a critical factor to local SEO. To help build authority, get your website listed on as many reputable directory or local citation sites like Yelp and Zagat as possible; here is a list of 50 to help save some time hunting these down. This list is only a sliver of such sites on the Web, so be sure to put in the leg work to gain additional listings. The more trustworthy citations you have pointing toward your site, the more authority you will gain. Additionally, tools like Synup, which is local-SEO focused, can help you accomplish this task in no time.