diff --git a/patacrep/content/include.py b/patacrep/content/include.py
index dbc10fce..9f27c992 100644
--- a/patacrep/content/include.py
+++ b/patacrep/content/include.py
@@ -28,18 +28,22 @@ def load_from_datadirs(path, datadirs):
         )
 
 #pylint: disable=unused-argument
-def parse(keyword, config, argument, contentlist):
+def parse(keyword, config, argument):
     """Include an external file content.
 
     Arguments:
         - keyword: the string 'include';
         - config: the current songbook configuration dictionary;
-        - argument: None;
-        - contentlist: a list of file paths to be included.
+        - argument:
+            a list of file paths to be included
+            or a string of the file to include
+
     """
     new_contentlist = ContentList()
+    if isinstance(argument, str):
+        argument = [argument]
 
-    for path in contentlist:
+    for path in argument:
         try:
             filepath = load_from_datadirs(path, config['_datadir'])
         except ContentError as error:
diff --git a/test/test_content/include.control b/test/test_content/include.control
index 5ba82a4c..2ee7f993 100644
--- a/test/test_content/include.control
+++ b/test/test_content/include.control
@@ -1 +1 @@
-["exsong.sg", "chordpro.csg", "subdir/chordpro.csg"]
\ No newline at end of file
+["exsong.sg", "chordpro.csg", "subdir/chordpro.csg", "exsong.sg", "chordpro.csg", "subdir/chordpro.csg"]
\ No newline at end of file
diff --git a/test/test_content/include.source b/test/test_content/include.source
index ccd69aa1..3a438e2a 100644
--- a/test/test_content/include.source
+++ b/test/test_content/include.source
@@ -1 +1,3 @@
-[["include" , "custom_list.json"]]
\ No newline at end of file
+- include:
+    - custom_list.json
+- include: custom_list.json
\ No newline at end of file
diff --git a/test/test_songbook/content.sb b/test/test_songbook/content.sb
index 4c57a262..5ff0bcca 100644
--- a/test/test_songbook/content.sb
+++ b/test/test_songbook/content.sb
@@ -16,4 +16,4 @@ content:
         - "song.csg"
         - "song.tsg"
         - ["tex", "foo.tex"]
-  - ["include", "include.sbc"]
\ No newline at end of file
+  - include: include.sbc
\ No newline at end of file