1) biblical: Using a statement from the bible, but not actually quoting it.
Example: "He was such a good samaritan yesterday when he helped carry the old ladies bags"
2) Literacy: a statement that indirectly refers to other well-known literary works.
Example: "I was suprised that Bob's nose didn't grow like Pinocchio's when he lied"
3) Historical: a statment that refers to history without directly mentioning it.
Example: "Because of a assassination, all the world was thrown into chaos" (WWI) ( Great War (1914-1918) )
4) Cultural: Association with a culture or group of people
Example: " He is like those rappers"
hope this helps