diff --git a/modules/Data_Summarization/Data_Summarization.Rmd b/modules/Data_Summarization/Data_Summarization.Rmd
index 091458002..6aa8d5cfd 100644
--- a/modules/Data_Summarization/Data_Summarization.Rmd
+++ b/modules/Data_Summarization/Data_Summarization.Rmd
@@ -297,6 +297,7 @@ summary(tb)
 
 💻 [Lab](https://jhudatascience.org/intro_to_r/modules/Data_Summarization/lab/Data_Summarization_Lab.Rmd)
 
+📃 [Day 4 Cheatsheet](https://jhudatascience.org/intro_to_r/modules/cheatsheets/Day-4.pdf)
 
 ## Youth Tobacco Survey
 
@@ -528,6 +529,8 @@ yts_loc %>% unique() %>% length() # similar to n_distinct()
 
 💻 [Lab](https://jhudatascience.org/intro_to_r/modules/Data_Summarization/lab/Data_Summarization_Lab.Rmd)
 
+📃 [Day 4 Cheatsheet](https://jhudatascience.org/intro_to_r/modules/cheatsheets/Day-4.pdf)
+
 ```{r, fig.alt="The End", out.width = "20%", echo = FALSE, fig.align='center'}
 knitr::include_graphics(here::here("images/the-end-g23b994289_1280.jpg"))
 ```