diff --git a/Readme.md b/Readme.md
index 3b39060..6956d47 100644
--- a/Readme.md
+++ b/Readme.md
@@ -24,7 +24,7 @@
 
 A minimal usable tokenizer written in XFST and following
 the guidelines to tokenizers in Beesley and Karttunen (2003)
-could look like this:
+and Beesley (2004) could look like this:
 
 ```xfst
 define TE "@_TOKEN_SYMBOL_@";
@@ -130,6 +130,9 @@
 
 Beesley, Kenneth R. & Lauri Karttunen (2003): *Finite State Morphology*. Stanford, CA: CSLI Publications.
 
+Beesley, Kenneth R. (2004): *Tokenizing Transducers*.
+[https://web.stanford.edu/~laurik/fsmbook/clarifications/tokfst.html](https://web.stanford.edu/~laurik/fsmbook/clarifications/tokfst.html)
+
 Hulden, Mans (2009): *Foma: a finite-state compiler and library*. In: Proceedings of the
 12th Conference of the European Chapter of the Association for Computational Linguistics,
 Association for Computational Linguistics, pp. 29-32.
@@ -140,4 +143,4 @@
 
 Kanda, Shunsuke, Yuma Fujita, Kazuhiro Morita & Masao Fuketa (2018):
 *Practical rearrangement methods for dynamic double-array dictionaries*.
-Software: Practice and Experience (SPE), 48(1), pp. 65–83.
\ No newline at end of file
+Software: Practice and Experience (SPE), 48(1), pp. 65–83.