In GOF Book, it says the structure of the Memento design pattern is like this:
![GOF Memento Pattern](https://ss0.bdstatic.com/70cFvHSh_Q1YnxGkpoWK1HF6hhy/it/u=2874087397,967157291&fm=26&gp=0.jpg)  

But when I searched Wikipedia, it says the structure of the Memento design pattern is like this:
![](https://upload.wikimedia.org/wikipedia/commons/3/38/W3sDesign_Memento_Design_Pattern_UML.jpg)

Which among the both is the correct implementation?