diff --git a/data/README.md b/data/README.md
index bb83b68..356298a 100644
--- a/data/README.md
+++ b/data/README.md
@@ -32,5 +32,7 @@ This directory contains preprocessed ISGRI detector count rate cleaned from the
 | B20 | 152.90-168.19 | detcnts.B20.fits |
 | B21 | 168.19-185.01 | detcnts.B21.fits |
 
+### cobe_ibis_resp_lon.dat
 
+This file comes from [Krivonos+ 2007](https://ui.adsabs.harvard.edu/abs/2007A%26A...463..957K/abstract) paper