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diff --git a/Concurrent Systems/notes/14.md b/Concurrent Systems/notes/14.md
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+++ b/Concurrent Systems/notes/14.md	
@@ -0,0 +1,6 @@
+We shall only consider finite processes (processes without recursive definitions)
+- a limited handling of recursion is possible
+- deciding bisimilarity for general processes is undecidable
+
+Inference system = axioms + inference rules
+- soundness;
\ No newline at end of file
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