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@@ -1,6 +1,6 @@
 # Teletype Model 33 ASR
 
-The [Teletype Model 33](https://en.wikipedia.org/wiki/Teletype_Model_33) was a very successful [computer terminal](https://en.wikipedia.org/wiki/Computer_terminal) in the late 1960s and 1970s.  It has an important historical role in several innovations, including the [ASCII  character set](https://en.wikipedia.org/wiki/ASCII) and the [development of Unix](https://homepage.cs.uri.edu/~thenry/resources/unix_art/ch02s01.html) and [BASIC](http://dtss.dartmouth.edu/).
+The [Teletype Model 33](https://en.wikipedia.org/wiki/Teletype_Model_33) was a very successful [computer terminal](https://en.wikipedia.org/wiki/Computer_terminal) in the late 1960s and 1970s.  It has an important historical role in several innovations, including the [ASCII  character set](https://en.wikipedia.org/wiki/ASCII) and the [development of Unix](https://web.archive.org/web/20220713165958/https://homepage.cs.uri.edu/~thenry/resources/unix_art/ch02s01.html) and [BASIC](http://dtss.dartmouth.edu/).
 
 [![teletype model 33](../pix/20180925_170552_x400.jpg)](../pix/20180925_170552.jpg)