diff --git a/source/repositories/calendar.ts b/source/repositories/calendar.ts
index 43266df..364f88f 100644
--- a/source/repositories/calendar.ts
+++ b/source/repositories/calendar.ts
@@ -41,6 +41,14 @@ namespace _zeitbild.repository.calendar
 	};
 	
 	
+	/**
+	 */
+	type type_access_attributed_group_preview = {
+		group_id : int;
+		level : int;
+	};
+	
+	
 	/**
 	 */
 	type type_access_attributed_user_row = {
@@ -50,6 +58,14 @@ namespace _zeitbild.repository.calendar
 	};
 	
 	
+	/**
+	 */
+	type type_access_attributed_user_preview = {
+		user_id : int;
+		level : int;
+	};
+	
+	
 	/**
 	 */
 	type type_dispersal = {
@@ -405,16 +421,18 @@ namespace _zeitbild.repository.calendar
 		const calendar_id : _zeitbild.type_calendar_id = await core_store.create(
 			dispersal.core_row
 		);
-		for await (const access_attributed_group_row of dispersal.access_attributed_group_rows) {
+		for await (const access_attributed_group_row of dispersal.access_attributed_group_rows)
+		{
 			get_access_attributed_group_chest().write(
-				[calendar_id, access_attributed_group_row["group_id"]],
-				{"level": access_attributed_group_row["level"]}
+				[calendar_id, access_attributed_group_row.group_id],
+				{"level": access_attributed_group_row.level}
 			);
 		}
-		for await (const access_attributed_user_row of dispersal.access_attributed_user_rows) {
+		for await (const access_attributed_user_row of dispersal.access_attributed_user_rows)
+		{
 			get_access_attributed_user_chest().write(
-				[calendar_id, access_attributed_user_row["user_id"]],
-				{"level": access_attributed_user_row["level"]}
+				[calendar_id, access_attributed_user_row.user_id],
+				{"level": access_attributed_user_row.level}
 			);
 		}
 		await lib_plankton.cache.clear(_zeitbild.cache_regular);
@@ -441,82 +459,114 @@ namespace _zeitbild.repository.calendar
 		// attributed:group
 		{
 			const access_attributed_group_chest = get_access_attributed_group_chest();
-			const hits : Array<Record<string, any>> = await access_attributed_group_chest.search(
-				{
-					"expression": "(calendar_id = $calendar_id)",
-					"arguments": {
-						"calendar_id": calendar_id,
+			const hits : Array<{key : Array<any>; preview : type_access_attributed_group_row;}> = (
+				(await access_attributed_group_chest.search(
+					{
+						"expression": "(calendar_id = $calendar_id)",
+						"arguments": {
+							"calendar_id": calendar_id,
+						}
 					}
-				}
+				))
+				.map(
+					hit => (
+						{
+							"key": hit.key,
+							"preview": {
+								"group_id": hit.preview["group_id"],
+								"level": hit.preview["level"],
+							}
+						}
+					)
+				)
 			);
 			const contrast = lib_plankton.list.contrast<
-				Record<string, any>,
-				Record<string, any>
+				{key : Array<any>; preview : type_access_attributed_group_row;},
+				type_access_attributed_group_row
 			>(
 				hits,
-				hit => hit["group_id"],
+				hit => hit.preview.group_id.toFixed(0),
 				dispersal.access_attributed_group_rows,
-				row => row["group_id"]
+				row => row.group_id.toFixed(0)
 			);
 			// delete
-			for await (const entry of contrast.only_left) {
+			for await (const entry of contrast.only_left)
+			{
 				await access_attributed_group_chest.delete(
-					[calendar_id, entry.left["group_id"]]
+					[calendar_id, entry.left.preview.group_id]
 				);
 			}
 			// update
-			for await (const entry of contrast.both) {
+			for await (const entry of contrast.both)
+			{
 				await access_attributed_group_chest.write(
-					[calendar_id, entry.right["group_id"]],
-					{"level": entry.right["level"]}
+					[calendar_id, entry.right.group_id],
+					{"level": entry.right.level}
 				);
 			}
 			// create
-			for await (const entry of contrast.only_right) {
+			for await (const entry of contrast.only_right)
+			{
 				await access_attributed_group_chest.write(
-					[calendar_id, entry.right["group_id"]],
-					{"level": entry.right["level"]}
+					[calendar_id, entry.right.group_id],
+					{"level": entry.right.level}
 				);
 			}
 		}
 		// attributed:user
 		{
 			const access_attributed_user_chest = get_access_attributed_user_chest();
-			const hits : Array<Record<string, any>> = await access_attributed_user_chest.search(
-				{
-					"expression": "(calendar_id = $calendar_id)",
-					"arguments": {
-						"calendar_id": calendar_id,
+			const hits : Array<{key : Array<any>; preview : type_access_attributed_user_row;}> = (
+				(await access_attributed_user_chest.search(
+					{
+						"expression": "(calendar_id = $calendar_id)",
+						"arguments": {
+							"calendar_id": calendar_id,
+						}
 					}
-				}
+				))
+				.map(
+					hit => (
+						{
+							"key": hit.key,
+							"preview": {
+								"user_id": hit.preview["user_id"],
+								"level": hit.preview["level"],
+							}
+						}
+					)
+				)
 			);
 			const contrast = lib_plankton.list.contrast<
-				Record<string, any>,
-				Record<string, any>
+				{key : Array<any>; preview : type_access_attributed_user_row;},
+				type_access_attributed_user_row
 			>(
 				hits,
-				hit => hit["user_id"],
+				hit => hit.preview.user_id.toFixed(0),
 				dispersal.access_attributed_user_rows,
-				row => row["user_id"]
+				row => row.user_id.toFixed(0)
 			);
 			// delete
-			for await (const entry of contrast.only_left) {
+			for await (const entry of contrast.only_left)
+			{
 				await access_attributed_user_chest.delete(
-					[calendar_id, entry.left["user_id"]]
+					[calendar_id, entry.left.preview.user_id]
 				);
 			}
 			// update
-			for await (const entry of contrast.both) {
+			for await (const entry of contrast.both)
+			{
 				await access_attributed_user_chest.write(
-					[calendar_id, entry.right["user_id"]],
-					{"level": entry.right["level"]}
+					[calendar_id, entry.right.user_id],
+					{"level": entry.right.level}
 				);
 			}
 			// create
-			for await (const entry of contrast.only_right) {
+			for await (const entry of contrast.only_right)
+			{
 				await access_attributed_user_chest.write(
-					[calendar_id, entry.right["user_id"]],
-					{"level": entry.right["level"]}
+					[calendar_id, entry.right.user_id],
+					{"level": entry.right.level}
 				);
 			}
 		}