diff --git a/README.md b/README.md
index b38ff58..2c519ed 100644
--- a/README.md
+++ b/README.md
@@ -124,6 +124,7 @@ the leap second!
 - [Why is subtracting these two times (in 1927) giving a strange result?](https://stackoverflow.com/a/6841479/57311) - Infamous
 Stack Overflow answer about both complicated historical timezones, and how
 historical dates can be re-interpreted by newer versions of software.
+- [Critical and Significant Dates](https://web.archive.org/web/20150908004245/http://www.merlyn.demon.co.uk/critdate.htm) - From Y2K to the overflow of 32-bit seconds from unix epoch, a list of special date to watch for depending on the system.
 
 
 ## Education