diff --git a/src/core/lib/Base91.mjs b/src/core/lib/Base91.mjs
index 3ee4c13a..9c1e3733 100644
--- a/src/core/lib/Base91.mjs
+++ b/src/core/lib/Base91.mjs
@@ -15,7 +15,7 @@ import OperationError from "../errors/OperationError.mjs";
 export const ALPHABET_OPTIONS = [
     {
         name: "Standard",
-        value: "A-Za-z0-9!#$%&()*+,./:;<=>?@[]^_`{|}~\"",
+        value: "A-Za-z0-9!#$%&()*+,./:;<=>?@[]^_`{|}~&quot;",
     }
 ];
 
diff --git a/tests/operations/index.mjs b/tests/operations/index.mjs
index 8d3cd623..42563016 100644
--- a/tests/operations/index.mjs
+++ b/tests/operations/index.mjs
@@ -23,6 +23,7 @@ import "./tests/BaconCipher.mjs";
 import "./tests/Base58.mjs";
 import "./tests/Base64.mjs";
 import "./tests/Base62.mjs";
+import "./tests/Base91.mjs";
 import "./tests/BitwiseOp.mjs";
 import "./tests/ByteRepr.mjs";
 import "./tests/CartesianProduct.mjs";
diff --git a/tests/operations/tests/Base91.mjs b/tests/operations/tests/Base91.mjs
index e52c5391..be962280 100644
--- a/tests/operations/tests/Base91.mjs
+++ b/tests/operations/tests/Base91.mjs
@@ -1,9 +1,9 @@
 /**
- * Base64 tests.
+ * Base91 tests.
  *
- * @author n1474335 [n1474335@gmail.com]
+ * @author idevlab [nidevlab@outlook.com]
  *
- * @copyright Crown Copyright 2018
+ * @copyright Crown Copyright 2020
  * @license Apache-2.0
  */
 import TestRegister from "../../lib/TestRegister.mjs";
@@ -15,7 +15,8 @@ TestRegister.addTests([
         expectedOutput: "idevlab",
         recipeConfig: [
             {
-                op: "From Base64"
+                op: "From Base91",
+                args: ["A-Za-z0-9!#$%&()*+,./:;<=>?@[]^_`{|}~&quot;"],
             },
         ],
     },