What is the author's style in The Garden of Forking Paths by Jorge Luis Borges?

One of the most interesting tricks Borges plays in "The Garden of Forking Paths" is his narrative technique. As the story opens, an unknown narrator speaks directly to the reader: "On page 22 of Liddell Hart's History of World War I you will read. . . ." The narrator summarizes Hart's position that rain delayed a British attack.