diff --git a/README.md b/README.md
index 5899f7a..f2683f7 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,29 @@
 # SwedishBankAccounts
 Validate Swedish Bank Accounts
+
+## Based on 
+  [bankernaskontonummeruppbyggnad_anvandarmanual_sv.pdf](https://www.bankgirot.se/globalassets/dokument/anvandarmanualer/bankernaskontonummeruppbyggnad_anvandarmanual_sv.pdf)
+  
+  [11-modul.pdf](https://www.bankgirot.se/globalassets/dokument/anvandarmanualer/11-modul.pdf)
+  
+  [10-modul.pdf](https://www.bankgirot.se/globalassets/dokument/anvandarmanualer/10-modul.pdf)
+
+## Usage
+
+            var account = new BankAccount(accountNumber);
+
+            if (!account.isValid)
+            {
+                Console.WriteLine("Account number invalid");
+                Console.WriteLine($"Reason: {account.ValidationResult.ToString()}");
+                return;
+            }
+
+            Console.WriteLine("Account number valid");
+            Console.WriteLine($"Validation result: {account.ValidationResult.ToString()}");
+            Console.WriteLine($"Bank: {account.BankName}");
+            Console.WriteLine($"Clearing number: {account.ClearingNumber}");
+            Console.WriteLine($"Account number:  {account.AccountNumber}");
+
+## Known issues
+Can not validate some Swedbank accounts with 5 digit clearing number.