diff --git a/COPYING b/COPYING
index 4d2513e..e114d20 100644
--- a/COPYING
+++ b/COPYING
@@ -1,3 +1,5 @@
 The code of the cmph library is dual licensed under the LGPL version 2 and MPL
 1.1 licenses. Please refer to the LGPL-2 and MPL-1.1 files in the repository
 for the full description of each of the licenses.
+
+For cxxmph, the files stringpiece.h and MurmurHash2 are covered by the BSD and MIT licenses, respectively.