Deletion of Headnote

Comment: Headnotes are a part of legal research tools. A quick  style search shows they are covered in reliable sources like books https://books.google.com/books?id=Lx7yq6BEmdsC&pg=PA85&dq=%22Headnote%22&hl=en&sa=X&ved=0ahUKEwinlvenjuraAhXCMGMKHaY7BQkQ6AEINzAC#v=onepage&q=%22Headnote%22&f=false, https://books.google.com/books?id=t_KkAwAAQBAJ&pg=PA72&dq=%22Headnote%22&hl=en&sa=X&ved=0ahUKEwinlvenjuraAhXCMGMKHaY7BQkQ6AEITTAG#v=onepage&q=%22Headnote%22&f=false. It looks like a notable topic per  and the article itself has no major problems, hence keep
Stance: keep
Cited policy: Wikipedia:Articles for deletion (WP:BEFORE||WP:GNG)