diff --git a/clusters/mitre-entreprise-attack-attack-pattern.json b/clusters/mitre-entreprise-attack-attack-pattern.json
index a71bf1e..852086d 100644
--- a/clusters/mitre-entreprise-attack-attack-pattern.json
+++ b/clusters/mitre-entreprise-attack-attack-pattern.json
@@ -3542,8 +3542,6 @@
           "https://source.winehq.org/WineAPI/samlib.html",
           "https://blog.stealthbits.com/manipulating-user-passwords-with-mimikatz-SetNTLM-ChangeNTLM",
           "https://msdn.microsoft.com/library/cc237008.aspx",
-          "https://adsecurity.org/?p=1729",
-          "http://www.harmj0y.net/blog/redteaming/mimikatz-and-dcsync-and-extrasids-oh-my/",
           "https://msdn.microsoft.com/library/cc245496.aspx"
         ],
         "mitre_data_sources": [
diff --git a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-attack-pattern_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-attack-pattern_galaxy.py
index 1d44735..0d736dd 100644
--- a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-attack-pattern_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-attack-pattern_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:                    
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:                    
                     value['meta']['refs'].append(reference['url'])
             if 'x_mitre_data_sources' in temp:
                 value['meta']['mitre_data_sources'] = temp['x_mitre_data_sources']
diff --git a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-intrusion-set_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-intrusion-set_galaxy.py
index b352c3e..805fe4a 100644
--- a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-intrusion-set_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-intrusion-set_galaxy.py
@@ -27,7 +27,7 @@ for element in os.listdir('.'):
             value['meta']['synonyms'] = temp['aliases']
             value['meta']['refs']= []
             for reference in temp['external_references']:
-                if 'url' in reference:                    
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:                    
                     value['meta']['refs'].append(reference['url'])
             value['uuid'] = re.search('--(.*)$', temp['id']).group(0)[2:]
             values.append(value)
diff --git a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-malware_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-malware_galaxy.py
index fe221ba..3f00538 100644
--- a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-malware_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-malware_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:
                     value['meta']['refs'].append(reference['url'])
             if'x_mitre_aliases' in temp:
                 value['meta']['synonyms'] = temp['x_mitre_aliases']     
diff --git a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-tool_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-tool_galaxy.py
index 5b7e221..65ea6bb 100644
--- a/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-tool_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-enterprise-attack-tool_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:
                     value['meta']['refs'].append(reference['url'])
             if'x_mitre_aliases' in temp:
                 value['meta']['synonyms'] = temp['x_mitre_aliases']     
diff --git a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-attack-pattern_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-attack-pattern_galaxy.py
index c6eef64..f4c04c5 100644
--- a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-attack-pattern_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-attack-pattern_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:                    
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:                    
                     value['meta']['refs'].append(reference['url'])
             if 'x_mitre_data_sources' in temp:
                 value['meta']['mitre_data_sources'] = temp['x_mitre_data_sources']
diff --git a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-intrusion-set_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-intrusion-set_galaxy.py
index 9ca5c38..345aa9f 100644
--- a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-intrusion-set_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-intrusion-set_galaxy.py
@@ -27,7 +27,7 @@ for element in os.listdir('.'):
             value['meta']['synonyms'] = temp['aliases']
             value['meta']['refs']= []
             for reference in temp['external_references']:
-                if 'url' in reference:                    
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:                    
                     value['meta']['refs'].append(reference['url'])
             value['uuid'] = re.search('--(.*)$', temp['id']).group(0)[2:]
             values.append(value)
diff --git a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-malware_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-malware_galaxy.py
index 2615cc3..d5fa491 100644
--- a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-malware_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-malware_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:
                     value['meta']['refs'].append(reference['url'])
             if'x_mitre_aliases' in temp:
                 value['meta']['synonyms'] = temp['x_mitre_aliases']     
diff --git a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-tool_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-tool_galaxy.py
index 9b409a1..d3082ab 100644
--- a/tools/mitre-cti/v2.0/create_mitre-mobile-attack-tool_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-mobile-attack-tool_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:
                     value['meta']['refs'].append(reference['url'])
             if'x_mitre_aliases' in temp:
                 value['meta']['synonyms'] = temp['x_mitre_aliases']     
diff --git a/tools/mitre-cti/v2.0/create_mitre-pre-attack-attack-pattern_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-pre-attack-attack-pattern_galaxy.py
index 9f691f2..a246896 100644
--- a/tools/mitre-cti/v2.0/create_mitre-pre-attack-attack-pattern_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-pre-attack-attack-pattern_galaxy.py
@@ -26,7 +26,7 @@ for element in os.listdir('.'):
             value['meta'] = {}
             value['meta']['refs'] = []
             for reference in temp['external_references']:
-                if 'url' in reference:                    
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:                    
                     value['meta']['refs'].append(reference['url'])
             if 'x_mitre_data_sources' in temp:
                 value['meta']['mitre_data_sources'] = temp['x_mitre_data_sources']
diff --git a/tools/mitre-cti/v2.0/create_mitre-pre-attack-intrusion-set_galaxy.py b/tools/mitre-cti/v2.0/create_mitre-pre-attack-intrusion-set_galaxy.py
index 696caa1..872c0d2 100644
--- a/tools/mitre-cti/v2.0/create_mitre-pre-attack-intrusion-set_galaxy.py
+++ b/tools/mitre-cti/v2.0/create_mitre-pre-attack-intrusion-set_galaxy.py
@@ -27,7 +27,7 @@ for element in os.listdir('.'):
             value['meta']['synonyms'] = temp['aliases']
             value['meta']['refs']= []
             for reference in temp['external_references']:
-                if 'url' in reference:                    
+                if 'url' in reference and reference['url'] not in value['meta']['refs']:                    
                     value['meta']['refs'].append(reference['url'])
             value['uuid'] = re.search('--(.*)$', temp['id']).group(0)[2:]
             values.append(value)