diff --git a/doc/appendix-de-kassensichv/examples/vouchers.md b/doc/appendix-de-kassensichv/examples/vouchers.md
index 421c82dc..2eb9d285 100644
--- a/doc/appendix-de-kassensichv/examples/vouchers.md
+++ b/doc/appendix-de-kassensichv/examples/vouchers.md
@@ -20,7 +20,8 @@ Request:
          "Amount":15.00,
          "VATRate":19.0000,
          // 0x4445000000000061 (coupon sales normal)
-         "ftChargeItemCase":4919338167972135009
+         "ftChargeItemCase":4919338167972135009,
+         "ftChargeItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       }
    ],
    "cbPayItems":[
@@ -64,7 +65,8 @@ Request (voucher within charge items):
          "Amount":-15.00,
          "VATRate":19.0000,
          // 0x4445000000000069 (coupon redeem normal)
-         "ftChargeItemCase":4919338167972135017
+         "ftChargeItemCase":4919338167972135017,
+         "ftChargeItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       }
    ],
    "cbPayItems":[],
@@ -100,6 +102,7 @@ Request (voucher within pay items):
          "Amount":15.00,
          // 0x4445 0000 0000 000A (internal / material consumption)         
          "ftPayItemCase":4919338167972134922
+         "ftPayItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       }
    ],
    // 0x4445 0000 0000 0001 (pos-receipt) + 0000 0001 0000 0000 (implicit flow)   
@@ -126,7 +129,8 @@ Request (voucher within pay items):
          "Description":"Voucher for food and drinks",
          "Amount":-150.00,
          // 0x4445 0000 0000 000D (voucher, not taxable)         
-         "ftPayItemCase":4919338167972134925
+         "ftPayItemCase":4919338167972134925,
+         "ftPayItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       },
       {
          "Quantity":1.0,
@@ -156,7 +160,8 @@ Request (voucher within charge items):
          "Description":"Voucher for food and drinks",
          "Amount":150.00,
          // 0x4445000000000060 (voucher sale not taxable)
-         "ftChargeItemCase":4919338167972135008
+         "ftChargeItemCase":4919338167972135008,
+         "ftChargeItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       }
    ],
    "cbPayItems":[
@@ -201,7 +206,8 @@ Request (voucher within pay items):
          "Description":"Voucher for food and drinks",
          "Amount":150.00,
          // 0x4445 0000 0000 000D (voucher, not taxable)         
-         "ftPayItemCase":4919338167972134925
+         "ftPayItemCase":4919338167972134925,
+         "ftChargeItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       },
       {
          "Quantity":1.0,
@@ -239,7 +245,8 @@ Request (voucher within charge items):
          "Description":"Voucher for food and drinks",
          "Amount":-150.00,
          // 0x4445000000000068 (voucher redeem not taxable)
-         "ftChargeItemCase":4919338167972135016
+         "ftChargeItemCase":4919338167972135016,
+         "ftChargeItemCaseData":"{\"VoucherNr\":\"UAUA91829182HH\"}"
       }
    ],
    "cbPayItems":[
diff --git a/doc/appendix-de-kassensichv/receipt-case-definitions/receipt-case-definitions.md b/doc/appendix-de-kassensichv/receipt-case-definitions/receipt-case-definitions.md
index 7e0ea7b9..f74a4960 100644
--- a/doc/appendix-de-kassensichv/receipt-case-definitions/receipt-case-definitions.md
+++ b/doc/appendix-de-kassensichv/receipt-case-definitions/receipt-case-definitions.md
@@ -22,3 +22,5 @@ The issuance of multi-purpose vouchers is covered within the pay items by `ftPay
 If the cash register can not handle the redemption within a pay item, then it can alternatively use a charge item having `ftChargeItemCase`: `0x4445000000000068`. 
 
 Furthermore for the issuance of multi-purpose vouchers, one can alternatively use a charge item instead of a pay item. The `ftChargeItemCase`: `0x4445000000000060` has to be used.
+
+For all voucher requests you can optionally submit the voucher number. It can be sent via `ftPayItemCaseData` or `ftChargeItemCaseData` in JSON format. To send, add the key value pair `VoucherNr` e.g. `"ftPayItemCaseData":"{ ..., "VoucherNr":"UAUA91829182HH", ... }"`.
\ No newline at end of file