diff --git a/CHANGELOG.md b/CHANGELOG.md
index 9fe4733f..d27232f8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,18 @@
 <!-- This file is generated, please add to it using `knope document-change` in the client-library-templates repo -->
 # Changelog
 
+## 9.1.0 (2026-09-17)
+
+### Features
+
+- Add "reference" to Create Bank Account Holder Verification
+
+## 9.0.4 (2026-09-16)
+
+### Fixes
+
+- Clean up docs and use a shared definition of event `include` and `resource_type` enums
+
 ## 9.0.3 (2026-09-14)
 
 ### Fixes
diff --git a/README.md b/README.md
index f85edc35..709dd93b 100644
--- a/README.md
+++ b/README.md
@@ -14,14 +14,14 @@ With Maven:
 <dependency>
     <groupId>com.gocardless</groupId>
     <artifactId>gocardless-pro</artifactId>
-    <version>9.0.3</version>
+    <version>9.1.0</version>
 </dependency>
 ```
 
 With Gradle:
 
 ```
-implementation 'com.gocardless:gocardless-pro:9.0.3'
+implementation 'com.gocardless:gocardless-pro:9.1.0'
 ```
 
 ## Initializing the client
diff --git a/build.gradle b/build.gradle
index 3a806bb8..e60d2060 100644
--- a/build.gradle
+++ b/build.gradle
@@ -29,7 +29,7 @@ plugins {
 sourceCompatibility = 1.8
 targetCompatibility = 1.8
 group = 'com.gocardless'
-version = '9.0.3'
+version = '9.1.0'
 
 apply plugin: 'ch.raffael.pegdown-doclet'
 
diff --git a/src/main/java/com/gocardless/http/HttpClient.java b/src/main/java/com/gocardless/http/HttpClient.java
index cca031df..7f70cac9 100644
--- a/src/main/java/com/gocardless/http/HttpClient.java
+++ b/src/main/java/com/gocardless/http/HttpClient.java
@@ -35,7 +35,7 @@ public class HttpClient {
     private static final String DISALLOWED_USER_AGENT_CHARACTERS =
             "[^\\w!#$%&'\\*\\+\\-\\.\\^`\\|~]";
     private static final String USER_AGENT =
-            String.format("gocardless-pro-java/9.0.3 java/%s %s/%s %s/%s",
+            String.format("gocardless-pro-java/9.1.0 java/%s %s/%s %s/%s",
                     cleanUserAgentToken(System.getProperty("java.vm.specification.version")),
                     cleanUserAgentToken(System.getProperty("java.vm.name")),
                     cleanUserAgentToken(System.getProperty("java.version")),
@@ -49,7 +49,7 @@ public class HttpClient {
         builder.put("GoCardless-Version", "2015-07-06");
         builder.put("Accept", "application/json");
         builder.put("GoCardless-Client-Library", "gocardless-pro-java");
-        builder.put("GoCardless-Client-Version", "9.0.3");
+        builder.put("GoCardless-Client-Version", "9.1.0");
         HEADERS = builder.build();
     }
     private final OkHttpClient rawClient;
diff --git a/src/main/java/com/gocardless/services/BankAccountHolderVerificationService.java b/src/main/java/com/gocardless/services/BankAccountHolderVerificationService.java
index 4e2b77e2..52d15281 100644
--- a/src/main/java/com/gocardless/services/BankAccountHolderVerificationService.java
+++ b/src/main/java/com/gocardless/services/BankAccountHolderVerificationService.java
@@ -49,6 +49,7 @@ public BankAccountHolderVerificationGetRequest get(String identity) {
     public static final class BankAccountHolderVerificationCreateRequest
             extends IdempotentPostRequest<BankAccountHolderVerification> {
         private Links links;
+        private String reference;
         private Type type;
 
         public BankAccountHolderVerificationCreateRequest withLinks(Links links) {
@@ -67,6 +68,15 @@ public BankAccountHolderVerificationCreateRequest withLinksBankAccount(String ba
             return this;
         }
 
+        /**
+         * An alphanumeric reference code used by some financial institutions to identify an
+         * individual account.
+         */
+        public BankAccountHolderVerificationCreateRequest withReference(String reference) {
+            this.reference = reference;
+            return this;
+        }
+
         /**
          * Type of the verification that has been performed eg. <a href=
          * "https://www.wearepay.uk/what-we-do/overlay-services/confirmation-of-payee/">Confirmation