diff --git a/Method.php b/Method.php
index 58a894b..49af0ac 100644
--- a/Method.php
+++ b/Method.php
@@ -2,6 +2,24 @@
 namespace Dfe\YandexKassa;
 // 2017-09-17
 final class Method extends \Df\PaypalClone\Method {
+	/**
+	 * 2017-09-17
+	 * The «sum» parameter has the «CurrencyAmount»:
+	 * https://tech.yandex.com/money/doc/payment-solution/payment-form/payment-form-http-docpage
+	 * https://tech.yandex.ru/money/doc/payment-solution/payment-form/payment-form-http-docpage
+	 * The «CurrencyAmount» type description:
+	 * In English: «Amount. Fixed-point decimal number with 2-digit precision.»
+	 * https://tech.yandex.com/money/doc/payment-solution/reference/datatypes-docpage
+	 * In Russian: «Сумма. Число с фиксированной точкой, две цифры после точки.»
+	 * https://tech.yandex.ru/money/doc/payment-solution/reference/datatypes-docpage
+	 * @override
+	 * @see \Df\Payment\Method::amountFormat()
+	 * @used-by \Df\Payment\Operation::amountFormat()
+	 * @param float|int $a
+	 * @return string
+	 */
+	function amountFormat($a) {return df_f2($a);}
+
 	/**
 	 * 2017-09-24
 	 * @used-by \Dfe\YandexKassa\Charge::pCharge()
diff --git a/composer.json b/composer.json
index 5e9ebc3..06718f0 100644
--- a/composer.json
+++ b/composer.json
@@ -1,6 +1,6 @@
 {
 	"name": "mage2pro/yandex-kassa"
-	,"version": "0.1.8"
+	,"version": "0.1.9"
 	,"description": "The «Yandex.Kassa» (Яндекс.Касса, Yandex.Checkout) payment extension for Magento 2."
 	,"type": "magento2-module"
 	,"homepage": "https://mage2.pro/c/extensions/yandex-kassa"