Note: EDU/GOV type of links are almost hardest links to find online. As most of edu sites and gov sites not give access or allow to build links. buy high da dofollow backlinks
EDU/Gov Links are considered "Trust Rank" or some people call it Authority links. It is best type of links for your site & help to build authority in Google.
The only reason Google rely on these type of sites, because Google know these sites gives/deliver always rely on these websites to offer quality content with only quality referencing.