diff --git a/app/resto/core/RestoCollection.php b/app/resto/core/RestoCollection.php
index 98adb1f4..8d76f59d 100755
--- a/app/resto/core/RestoCollection.php
+++ b/app/resto/core/RestoCollection.php
@@ -1114,9 +1114,14 @@ private function checkCreationMandatoryProperties($object, $modelName)
         }
          
         /*
-         * Set DefaultModel if not set
+         * Set DefaultModel if not set - preseance to input $modelName
          */
-        $object['model'] = isset($modelName) ? $modelName : ($object['model'] ?? 'DefaultModel');
+        if ( isset($modelName) ) {
+            $object['model'] = $modelName;
+        }
+        if ( !isset($object['model']) ) {
+            $object['model'] = $this->context->core['defaultModel'];
+        }
         
         if (!class_exists($object['model']) || !is_subclass_of($object['model'], 'RestoModel')) {
             RestoLogUtil::httpError(400, 'Model "' . $object['model'] . '" is not a valid model name');
diff --git a/app/resto/core/RestoConstants.php b/app/resto/core/RestoConstants.php
index 1efbc9a0..6f9e078b 100644
--- a/app/resto/core/RestoConstants.php
+++ b/app/resto/core/RestoConstants.php
@@ -20,7 +20,7 @@ class RestoConstants
     // [IMPORTANT] Starting resto 7.x, default routes are defined in RestoRouter class
 
     // resto version
-    const VERSION = '9.0.4';
+    const VERSION = '9.0.5';
 
     /* ============================================================
      *              NEVER EVER TOUCH THESE VALUES
diff --git a/app/resto/core/RestoContext.php b/app/resto/core/RestoContext.php
index 60af588b..186a7d4f 100755
--- a/app/resto/core/RestoContext.php
+++ b/app/resto/core/RestoContext.php
@@ -53,6 +53,9 @@ class RestoContext
         // Display collection that have at least 'collectionMinMatch' object
         'collectionMinMatch' => 0,
 
+        // Default model applied to POST collection
+        'defaultModel' => 'DefaultModel',
+
         // Use cache
         'useCache' => false,
 
diff --git a/app/resto/core/api/CollectionsAPI.php b/app/resto/core/api/CollectionsAPI.php
index 415f53e4..f37042c5 100755
--- a/app/resto/core/api/CollectionsAPI.php
+++ b/app/resto/core/api/CollectionsAPI.php
@@ -491,7 +491,7 @@ public function deleteCollection($params)
             RestoLogUtil::httpError(403);
         }
 
-        (new CollectionsFunctions($this->context->dbDriver))->removeCollection($collection);
+        (new CollectionsFunctions($this->context->dbDriver))->removeCollection($collection, $this->context->core['baseUrl']);
 
         return RestoLogUtil::success('Collection ' . $collection->id . ' deleted');
     }
diff --git a/app/resto/core/api/STACAPI.php b/app/resto/core/api/STACAPI.php
index c2904b12..9dc31c73 100644
--- a/app/resto/core/api/STACAPI.php
+++ b/app/resto/core/api/STACAPI.php
@@ -405,8 +405,10 @@ public function addCatalog($params, $body)
          * [IMPORTANT] Special case - post a collection under a catalog is in fact an update of 'links' property of this catalog
          */
         if ( $body['type'] === 'Collection' ) {
+
+            // Collection does not exist - created first
             if ( !(new CollectionsFunctions($this->context->dbDriver))->collectionExists($body['id']) ) {
-                return RestoLogUtil::httpError(400, 'Collection ' . $body['id'] . ' does not exist. Should be added first before pushing under a catalog');
+                $this->context->keeper->getRestoCollections($this->user)->create($body, $params['model'] ?? null);
             }
             return $this->catalogsFunctions->storeCollectionUnderCatalog($parentId, $body['id'], $this->user->profile['id'], $this->context) ? RestoLogUtil::success('Collection added under catalog ' . $parentId) : RestoLogUtil::error('Cannot add collection under catalog ' . $parentId);
         }
diff --git a/app/resto/core/dbfunctions/CatalogsFunctions.php b/app/resto/core/dbfunctions/CatalogsFunctions.php
index b5c1a1de..6f41ab17 100755
--- a/app/resto/core/dbfunctions/CatalogsFunctions.php
+++ b/app/resto/core/dbfunctions/CatalogsFunctions.php
@@ -282,6 +282,7 @@ public function storeCollectionUnderCatalog($catalogId, $collectionId, $userid,
 
         $link = array(
             'rel' => 'child',
+            'type' => RestoUtil::$contentTypes['json'],
             'href' => $context->core['baseUrl'] . RestoRouter::ROUTE_TO_COLLECTIONS . '/' . $collectionId
         );
 
diff --git a/app/resto/core/dbfunctions/CollectionsFunctions.php b/app/resto/core/dbfunctions/CollectionsFunctions.php
index 0b85b9bb..26d310f8 100755
--- a/app/resto/core/dbfunctions/CollectionsFunctions.php
+++ b/app/resto/core/dbfunctions/CollectionsFunctions.php
@@ -130,10 +130,10 @@ public function collectionExists($collectionId)
      * Remove collection from RESTo database
      *
      * @param RestoCollection $collection
-     * @return array
+     * @param string $baseUrl
      * @throws Exception
      */
-    public function removeCollection($collection)
+    public function removeCollection($collection, $baseUrl)
     {
         /*
          * Never remove a non empty collection
@@ -146,8 +146,14 @@ public function removeCollection($collection)
          * Delete (within transaction)
          */
         try {
+
             $this->dbDriver->query('BEGIN');
 
+            /*
+             * First remove collection referenced within catalogs
+             */
+            $this->removeCollectionFromCatalogs($baseUrl . RestoRouter::ROUTE_TO_COLLECTIONS . '/' . $collection->id);
+            
             $this->dbDriver->pQuery('DELETE FROM ' . $this->dbDriver->targetSchema . '.collection WHERE id=$1', array(
                 $collection->id
             ));
@@ -630,4 +636,55 @@ private function format($rawDescription, $osDescription)
 
         return $collection;
     }
+
+    /**
+     * 
+     * Remove all collectionUrl entries in catalog links property
+     * 
+     * @param string $collectionurl
+     * @return void
+     */
+    private function removeCollectionFromCatalogs($collectionurl)
+    {
+        
+        $this->dbDriver->query("WITH tmp AS (
+            WITH target_links as (
+                SELECT id, links
+                FROM " . $this->dbDriver->targetSchema . ".catalog
+                WHERE EXISTS (
+                    SELECT 1
+                    FROM json_array_elements(links) AS link
+                    WHERE link->>'href' = '" . $collectionurl . "'
+                )
+            ),
+            expanded_links AS (
+                SELECT
+                    id,
+                    json_array_elements(links) AS link
+                FROM target_links
+                WHERE json_typeof(links) = 'array'
+            ),
+            filtered_links AS (
+                SELECT
+                    id,
+                    json_agg(link) AS new_links
+                FROM expanded_links
+                WHERE link->>'href' != '" . $collectionurl . "' -- Exclude the link with the specific ID
+                GROUP BY id
+            )
+            SELECT " . $this->dbDriver->targetSchema . ".catalog.id, f.new_links AS modified_links
+            FROM " . $this->dbDriver->targetSchema . ".catalog
+            LEFT JOIN filtered_links f ON " . $this->dbDriver->targetSchema . ".catalog.id = f.id
+        )
+        UPDATE " . $this->dbDriver->targetSchema . ".catalog
+        SET links = tmp.modified_links
+        FROM tmp
+        WHERE " . $this->dbDriver->targetSchema . ".catalog.id = tmp.id
+        AND EXISTS (
+            SELECT 1
+            FROM json_array_elements(links) AS link
+            WHERE link->>'href' = '" . $collectionurl .  "'
+        );");
+
+    }
 }
diff --git a/build/resto/config.php.template b/build/resto/config.php.template
index 2323b9fb..ad3053ac 100755
--- a/build/resto/config.php.template
+++ b/build/resto/config.php.template
@@ -12,6 +12,7 @@ return array(
     ),
     'storeQuery' => ${STORE_QUERY:-false},
     'collectionMinMatch' => ${COLLECTION_MINMATCH:-0},
+    'defaultModel' => '${DEFAULT_COLLECTION_MODEL:-DefaultModel}',
     'timezone' => '${TIMEZONE:-Europe/Paris}',
     'tokenDuration' => ${JWT_DURATION:-8640000},
     'userAutoValidation' => ${USER_AUTOVALIDATION:-true},
diff --git a/config.env b/config.env
index 89409fdd..124117db 100644
--- a/config.env
+++ b/config.env
@@ -27,6 +27,9 @@ SUPPORTED_LANGUAGES=en,fr
 ### Data related "planet"
 #PLANET=earth
 
+### Default Model applied to collection
+#DEFAULT_COLLECTION_MODEL=DefaultModel
+
 ### Permanent storage directory to store/retrieve files (e.g. user's avatar picture)
 ### Relative to PUBLIC_ENDPOINT if not starting with http
 #STORAGE_PUBLIC_ENDPOINT=/static
diff --git a/examples/collections/DummyCollection.json b/examples/collections/DummyCollection.json
index 24d66adb..f6be1cd3 100644
--- a/examples/collections/DummyCollection.json
+++ b/examples/collections/DummyCollection.json
@@ -5,7 +5,6 @@
         "DummyCollectionAlias"
     ],
     "version": "1.0",
-    "model": "OpticalModel",
     "license": "PDDL-1.0",
     "osDescription": {
         "en": {
diff --git a/examples/collections/DummyCollection2.json b/examples/collections/DummyCollection2.json
new file mode 100644
index 00000000..adc69d05
--- /dev/null
+++ b/examples/collections/DummyCollection2.json
@@ -0,0 +1,27 @@
+{
+    "id": "DummyCollection2",
+    "type": "Collection",
+    "version": "1.0",
+    "license": "PDDL-1.0",
+    "osDescription": {
+        "en": {
+            "ShortName": "DummyCollection2",
+            "LongName": "DummyCollection2",
+            "Description": "This is a Dummy Collection2",
+            "Tags": "dummy",
+            "Developer": "Jérôme Gasperi",
+            "Contact": "jrom@snapplanet.io",
+            "Query": "dummy",
+            "Attribution": "USGS/NASA Landsat"
+        }
+    },
+    "providers": [
+        {
+            "name": "jeobrowser",
+            "roles": [
+                "processor"
+            ],
+            "url": "https://github.com/jjrom/resto"
+        }
+    ]
+}
\ No newline at end of file