diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7920974..647266f 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,9 @@
-## [Unreleased]
+## [0.1.1] - 2023-06-19
 
-## [0.1.0] - 2023-06-15
+- Fix typo in a `README.md` file
+- add ability to pass reference to an invoice by `reference` parameter in a `MonopayRuby::Invoices::SimpleInvoice::create` method
+- Use named parameter of `destionation` for "MonopayRuby::Invoices::SimpleInvoice::create" method
 
-- Initial release
+## [0.1.0] - 2023-06-18
+
+- Initial public release
diff --git a/Gemfile.lock b/Gemfile.lock
index e92dcb3..c95ea4c 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    monopay-ruby (0.1.0)
+    monopay-ruby (0.1.1)
       base64 (~> 0.1.1)
       json (~> 2.5)
       money (~> 6.13)
diff --git a/lib/monopay-ruby/invoices/simple_invoice.rb b/lib/monopay-ruby/invoices/simple_invoice.rb
index eef4157..c8fa0c6 100644
--- a/lib/monopay-ruby/invoices/simple_invoice.rb
+++ b/lib/monopay-ruby/invoices/simple_invoice.rb
@@ -4,11 +4,11 @@
 module MonopayRuby
   module Invoices
     class SimpleInvoice < MonopayRuby::Base
-      attr_reader :invoice_id, :page_url, :error_messages, :amount, :destination, :redirect_url, :webhook_url
+      attr_reader :invoice_id, :page_url, :error_messages, :amount, :destination, :reference, :redirect_url, :webhook_url
 
       API_CREATE_INVOICE_URL = "#{API_URL}/merchant/invoice/create".freeze
 
-      CURRENCY = "UAH".freeze
+      DEFAULT_CURRENCY = "UAH".freeze
 
       PAGE_URL_KEY = "pageUrl".freeze
       INVOICE_ID_KEY = "invoiceId".freeze
@@ -28,11 +28,13 @@ def initialize(redirect_url = nil, webhook_url = nil)
       #
       # @param [BigDecimal,Integer] amount in UAH (cents) to request payment
       # @param [String] destination - additional info about payment
+      # @param [String] reference - bill number or other reference
       # @return [Boolean] true if invoice was created successfully, false otherwise
-      def create(amount, destination = nil)
+      def create(amount, destination: nil, reference: nil)
         begin
           @amount = convert_to_cents(amount)
           @destination = destination
+          @reference = reference
 
           response = RestClient.post(API_CREATE_INVOICE_URL, request_body, headers)
           response_body = JSON.parse(response.body)
@@ -64,6 +66,7 @@ def request_body
           redirectUrl: redirect_url,
           webHookUrl: webhook_url,
           merchantPaymInfo: {
+            reference: reference,
             destination: destination
           }
         }.to_json
@@ -71,7 +74,7 @@ def request_body
 
       def convert_to_cents(amount)
         if amount.is_a?(BigDecimal)
-          Money.from_amount(amount, CURRENCY).cents
+          Money.from_amount(amount, DEFAULT_CURRENCY).cents
         else
           amount
         end
diff --git a/lib/monopay-ruby/version.rb b/lib/monopay-ruby/version.rb
index 5aee55f..c8194d3 100644
--- a/lib/monopay-ruby/version.rb
+++ b/lib/monopay-ruby/version.rb
@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module MonopayRuby
-  VERSION = "0.1.0"
+  VERSION = "0.1.1"
 end