diff --git a/lib/function/construction/matrix.js b/lib/function/construction/matrix.js
index d6c32d439..52000e0a2 100644
--- a/lib/function/construction/matrix.js
+++ b/lib/function/construction/matrix.js
@@ -60,6 +60,7 @@ module.exports = function (math) {
    *    bignumber, boolean, complex, index, number, string, unit
    *
    * @param {Array | Matrix} [data]    A multi dimensional array
+   * @param {string} [format]          The Matrix storage format
    * @return {Matrix} The created matrix
    */
   math.matrix = function matrix(data, format) {