diff --git a/Tranga/Publication.cs b/Tranga/Publication.cs
index 9abfae9..b378f60 100644
--- a/Tranga/Publication.cs
+++ b/Tranga/Publication.cs
@@ -1,4 +1,5 @@
-using Newtonsoft.Json;
+using System.Text;
+using Newtonsoft.Json;
 
 namespace Tranga;
 
@@ -35,7 +36,8 @@ public readonly struct Publication
         this.status = status;
         this.downloadUrl = downloadUrl;
         this.folderName = string.Concat(sortName.Split(Path.GetInvalidPathChars().Concat(Path.GetInvalidFileNameChars()).ToArray()));
-        this.internalId = Guid.NewGuid().ToString();
+        string onlyLowerAscii = this.sortName.ToLower().Where(Char.IsAscii).ToString()!;
+        this.internalId = Convert.ToBase64String(Encoding.ASCII.GetBytes($"{onlyLowerAscii}{this.year}"));
     }
     
     /// <returns>Serialized JSON String for series.json</returns>