diff --git a/src/ro_crate.py b/src/ro_crate.py
index 935f5414dc8bef361e1b15e144296a0219c745ea..c0bc1840044a8c7713643be55e53140fe34346f9 100644
--- a/src/ro_crate.py
+++ b/src/ro_crate.py
@@ -159,11 +159,12 @@ class RO_Crate:
         
         """
         if(self.license==None):
-            try:
-                res = self.info_dico_workflow["license"]["key"]
-            except:
-                res = None
-            return res
+            raise Exception("License is not given -> give it from list list https://spdx.org/licenses/")
+            #try:
+            #    res = self.info_dico_workflow["license"]["key"]
+            #except:
+            #    res = None
+            #return res
         else:
             return self.license
         
@@ -264,7 +265,9 @@ class RO_Crate:
         root["description"] = str(self.get_description())
         root["mainEntity"] = {"@id": str(self.workflow.get_first_file().get_file_address()).split("/")[-1]}
                               #, "@type":["File", "SoftwareSourceCode"]} #We do not consider a File as a "ComputationalWorkflow" since multiple (sub)workflows can be defined in a same file
-        root["license"] = {"@id":str(self.get_license())}
+        license = str(self.get_license())
+        root["license"] = license
+        #self.dico["@graph"].append({"@id":license, "@type":['License'], "name":"MIT"})
         authors = self.get_authors()
         tab_authors, tab_authors_ids= [], []
         for author in authors:
@@ -369,7 +372,7 @@ class RO_Crate:
         creators = self.get_creators(key)
         dico["creator"] = []
         for creator in creators:
-            dico["creator"].append({"@id": creator["@id"]})
+            dico["creator"].append({"@id": f'#{creator["@id"]}'})
         dico["isPartOf"] = []
         dico["hasPart"] = []
         self.dico["@graph"].append(dico)    
diff --git a/src/workflow.py b/src/workflow.py
index 7f66578065daa2772db8cb8e743ee4a7a42245e7..fc408509b47cf99901b8dd0a76baa7120e568155 100644
--- a/src/workflow.py
+++ b/src/workflow.py
@@ -303,8 +303,17 @@ George Marchment, Bryan Brancotte, Marie Schmit, Frédéric Lemoine, Sarah Cohen
     #The generation of the Ro-Crate has been valid from 
     # - https://ro-crate.ldaca.edu.au/explorer, and
     # - https://github.com/crs4/rocrate-validator (with the workflow-ro-crate-1.0 profile) 
-    def get_rocrate(self, display_info=False):
-        self.rocrate = RO_Crate(self, display_info=display_info)
+    def get_rocrate(self, display_info=False, personnal_acces_token = None,
+                    datePublished=None, description=None,
+                  license=None, authors = None,
+                   publisher = None, keywords = None,
+                   producer = None):
+        
+        self.rocrate = RO_Crate(self, display_info=display_info, personnal_acces_token = personnal_acces_token,
+                 datePublished=datePublished, description=description,
+                  license=license, authors = authors,
+                   publisher = publisher, keywords = keywords,
+                   producer = producer)
         self.rocrate.initialise()