diff --git a/THANKS b/THANKS
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--- a/THANKS
+++ b/THANKS
@@ -1,5 +1,7 @@
 The Guile core distribution:
 
+Mikael Djurfeldt and Christian Lynbech contributed core support for GOOPS,
+    a CLOS-like object system.
 Gary Houston contributed a new, more efficient implementation of I/O ports,
     and hacked on (ice-9 expect).
 Michael Livshin implemented Dybvig's Guardians.