Update README.md

README.md

@@ -14,8 +14,8 @@
  - If you got inspired by existing solutions to this problem, it's perfectly fine, but please say so, give them credit and explain how does your approach differ!
 - Present your project to the rest of the class in the last lecture.
 
-####
-
+#### Choosing ideal vector size
+https://aclanthology.org/I17-2006.pdf
 
 #### Evaluation techniques
 https://towardsdatascience.com/clustering-documents-with-python-97314ad6a78d