diff --git a/plt/README.md b/plt/README.md
index 9ef0e68..33d8c83 100644
--- a/plt/README.md
+++ b/plt/README.md
@@ -5,3 +5,5 @@
 * [Programming and Reasoning with Algebraic Effects and Dependent Types](http://eb.host.cs.st-andrews.ac.uk/drafts/effects.pdf)
 
 * [Programming Languages: History and Future](http://www.csee.umbc.edu/courses/undergraduate/CMSC331/resources/papers/sammet1972.pdf)
+
+* [Soft Typing](http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.24.9333&rep=rep1&type=pdf)