The writer's world is another way of saying; "The scene that is being set for the story to be told. Time, Location, Characters, Mood, Situation, etc.
For example, If you were telling a story about Dungeons and Dragons, perhaps you would mention that the main characters, Corlon, a Fighter and Esmerelda, a Sorceress are Trapped in a Dragon's Cave guarded by a Large one-eyed Cyclops and a Very Large Hungry Green Dragon. And so on.
The answer is:
Epstein, David. "Beat by an Underhand Girl." The Sports Gene. Penguin Group, 2013.
When writing references, the surname and name or initials of the author goes first. Next the title of the chapter within quotation marks, followed by the name of the book, publisher and year.
Exposition provides reader with information, sometimes it is nonessential info and can be revealed simply with exposition dialogue
