diff --git a/doc/src/file-icatdata.rst b/doc/src/file-icatdata.rst
index 31cfba9..54e045b 100644
--- a/doc/src/file-icatdata.rst
+++ b/doc/src/file-icatdata.rst
@@ -67,5 +67,5 @@ file.  The related object must have its own entry.
 
 
 .. [#dc] There is one exception: DataCollections don't have a
-	 uniqueness constraint and can't reliably be searched by
-	 attributes.  They are always kept in the index.
+         uniqueness constraint and can't reliably be searched by
+         attributes.  They are always kept in the index.