diff --git a/CHANGELOG.md b/CHANGELOG.md
index 4986026..ceca8b5 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+## [1.1.1] - 2020-12-27
+### Fix
+* Fix validator to cover isbn-10 special case (ends with "X")
 ## [1.1.0] - 2020-09-07
 ### Added
 * Add "prefix" option to generator to produce output with or without 'isbn-[type]: ' string.
diff --git a/__test__/validator.test.js b/__test__/validator.test.js
index 81a51c2..c2a3c5d 100644
--- a/__test__/validator.test.js
+++ b/__test__/validator.test.js
@@ -8,6 +8,7 @@ test('validator should return TRUE if passed value is a valid 10 numbers ISBN ',
   expect(validator('84   481         2231        3')).toBe(true);
   expect(validator('8448122313')).toBe(true);
   expect(validator('84-481-2231-3')).toBe(true);
+  expect(validator('006095485X')).toBe(true);
 });
 
 test('should return FALSE if passed string does not have the correct lenght', () => {
diff --git a/package.json b/package.json
index 528c806..17a43b8 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "isbn-util",
-  "version": "1.1.0",
+  "version": "1.1.1",
   "description": "",
   "main": "index.js",
   "scripts": {
diff --git a/src/validator.js b/src/validator.js
index 1de8f05..74798f1 100644
--- a/src/validator.js
+++ b/src/validator.js
@@ -9,16 +9,18 @@ const hasCorrectFormat = value => value.length === validLengths.MIN || value.len
 const IsValidIsbn = isbn => {
   let result = false;
   const isbnAsArray = Array.from(isbn);
+  const controlDigit = isbnAsArray.pop();
 
   if (isbn.length === validLengths.MIN ) {
     const sumOfIsbnNumbers = isbnAsArray.map((el, index) => {
       return el * (index + 1);
     }).reduce((acc, curr) => acc + curr );
 
-    result = (sumOfIsbnNumbers % 11) === 0;
+    const modulus = sumOfIsbnNumbers % 11;
+
+    result = controlDigit.toUpperCase() === 'X' ? modulus === 10 : modulus === parseInt(controlDigit);
 
   } else {
-    const controlDigit = isbnAsArray.pop();
     const elementsSum = isbnAsArray.map((el, index) => (index + 1) % 2 === 0 ? el * 1 : el * 3).reduce((acc, curr) => acc + curr);
     const sumModule = elementsSum % 10;