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@@ -163,6 +163,7 @@ On character encoding, string formatting, unicode and internationalization.
 - [Falsehoods about Networks](http://blog.erratasec.com/2012/06/falsehoods-programmers-believe-about.html) - Covers TCP, DHCP, DNS, VLANs and IPv4/v6.
 - [Fallacies of Distributed Computing](https://en.wikipedia.org/wiki/Fallacies_of_distributed_computing) - Assumptions that programmers new to distributed applications invariably make.
 - [There's more than one way to write an IP address](https://ma.ttias.be/theres-more-than-one-way-to-write-an-ip-address/) - Some parts of the address are optional, mind the decimal and octal notations, and [don't forget IPv6](https://news.ycombinator.com/item?id=20390981) either.
+- [IDN is crazy](https://daniel.haxx.se/blog/2022/12/14/idn-is-crazy/) - International characters in domain names mean support of homographs and heterographs.
 - [`hostname-validate`](https://github.com/jakeogh/hostname-validate) - An attempt to validate hostnames in Python.
 
 ## Phone Numbers