Update README.md

README.md

@@ -17,7 +17,7 @@ Our mission is to develop efficient, effective, and accessible spaced repetition
 
 ## Origin
 
-FSRS originates in [the DHP model from MaiMemo](https://www.maimemo.com/paper/) which is a variant of the DSR (Difficulty, Stability, Retrievability) model used to predict memory states. Here are the papers:
+FSRS originates in [the DHP model from MaiMemo](https://www.maimemo.com/paper/) which is a variant of the DSR (Difficulty, Stability, Retrievability) model used to predict memory states. Here are the original papers:
 
   - [Maimemo: A Stochastic Shortest Path Algorithm for Optimizing Spaced Repetition Scheduling - Proceedings of the 28th ACM SIGKDD Conference on Knowledge Discovery and Data Mining](https://dl.acm.org/doi/10.1145/3534678.3539081?cid=99660547150)
   - [Maimemo: Optimizing Spaced Repetition Schedule by Capturing the Dynamics of Memory - IEEE Journals & Magazine - IEEE Xplore](https://drive.google.com/file/d/1riJbkH39JB71Wj0AzESTngUM0LaeoD2l/view)