diff --git a/doc/ess/fieldmap.rst b/doc/ess/fieldmap.rst
new file mode 100644
index 0000000000000000000000000000000000000000..424e49ddc924ae14aaf19d31def9aa9577a8173e
--- /dev/null
+++ b/doc/ess/fieldmap.rst
@@ -0,0 +1,7 @@
+ess.fieldmap
+----------------
+
+Main description of this module is not written yet
+
+.. automodule:: ess.lib_tw
+    :members:
diff --git a/doc/ess/index.rst b/doc/ess/index.rst
index 3a5ab6aaca8f22b2bc89b8791678b4959f3499ce..5d9d38df7a959a1e85bb76431b638a4ae31855c3 100644
--- a/doc/ess/index.rst
+++ b/doc/ess/index.rst
@@ -1,12 +1,14 @@
 API Reference
 *************
 
-Two main libraries
+Three main libraries
 
 * :class:`ess.lib_tw` TraceWin library originally from Ryoichi
 
 * :class:`ess.TraceWin` TraceWin library originally from Yngve
 
+* :class:`ess.fieldmap` fieldmap manipulation library from Mamad
+
 
 
 .. toctree::
@@ -14,3 +16,4 @@ Two main libraries
 
    TraceWin
    lib_tw
+   fieldmap