diff --git a/include/boost/iostreams/device/file_descriptor.hpp b/include/boost/iostreams/device/file_descriptor.hpp
index 40fa59e..1ffc990 100755
--- a/include/boost/iostreams/device/file_descriptor.hpp
+++ b/include/boost/iostreams/device/file_descriptor.hpp
@@ -20,7 +20,7 @@
 #include <boost/iostreams/detail/config/auto_link.hpp>
 #include <boost/iostreams/detail/config/dyn_link.hpp>
 
-// Must be the last header.
+// Must come last.
 #include <boost/config/abi_prefix.hpp>     
 
 namespace boost { namespace iostreams {
diff --git a/include/boost/iostreams/device/mapped_file.hpp b/include/boost/iostreams/device/mapped_file.hpp
index 8e8f648..b277c6f 100755
--- a/include/boost/iostreams/device/mapped_file.hpp
+++ b/include/boost/iostreams/device/mapped_file.hpp
@@ -44,7 +44,7 @@
 #include <boost/iostreams/detail/config/dyn_link.hpp>
 #include <boost/shared_ptr.hpp>
 
-// Must be the last headers.
+// Must come last.
 #include <boost/iostreams/detail/disable_warnings.hpp>
 #include <boost/config/abi_prefix.hpp>