diff --git a/.travis.yml b/.travis.yml
index 88968815..d9f3ffd2 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ install:
   - go get -d -t -v ./... && go build -v ./...
 
 go:
+  - 1.5
   - 1.6
   - 1.7
   - tip
diff --git a/README.md b/README.md
index 0935d479..0bd7c028 100644
--- a/README.md
+++ b/README.md
@@ -7,15 +7,17 @@
 [![GoDoc](https://godoc.org/github.com/Luxurioust/excelize?status.svg)](https://godoc.org/github.com/Luxurioust/excelize)
 [![Licenses](https://img.shields.io/badge/license-bsd-orange.svg)](https://opensource.org/licenses/BSD-3-Clause)
 [![Join the chat at https://gitter.im/xuri-excelize/Lobby](https://img.shields.io/badge/GITTER-join%20chat-green.svg)](https://gitter.im/xuri-excelize/Lobby)
- 
+
 ## Introduction
 
-Excelize is a library written in pure Golang and providing a set of function that allow you to write to and read from XLSX files. The full API docs can be viewed using go’s built in documentation tool, or online at [godoc.org](https://godoc.org/github.com/Luxurioust/excelize).
+Excelize is a library written in pure Golang and providing a set of function that allow you to write to and read from XLSX files. Support read and write XLSX file geterated by Office Excel 2007 and later. The full API docs can be viewed using go’s built in documentation tool, or online at [godoc.org](https://godoc.org/github.com/Luxurioust/excelize).
 
 ## Basic Usage
 
 ### Installation
 
+Golang version requirements 1.6.0 or higher.
+
 ```
 go get github.com/Luxurioust/excelize
 ```
@@ -58,7 +60,7 @@ import (
 )
 
 func main() {
-    xlsx, err := excelize.Openxlsx("~/Workbook.xlsx")
+    xlsx, err := excelize.OpenFile("~/Workbook.xlsx")
     if err != nil {
         fmt.Println(err)
     }
diff --git a/excelize_test.go b/excelize_test.go
index c2848a05..b392264b 100644
--- a/excelize_test.go
+++ b/excelize_test.go
@@ -2,20 +2,10 @@ package excelize
 
 import (
 	"fmt"
-	"math/rand"
-	"sync"
+	"strconv"
 	"testing"
-	"time"
 )
 
-var (
-	once sync.Once
-)
-
-func testSetup() {
-	rand.Seed(time.Now().UnixNano())
-}
-
 func TestExcelize(t *testing.T) {
 	// Test update a XLSX file
 	file, err := OpenFile("./test/Workbook1.xlsx")
@@ -32,7 +22,7 @@ func TestExcelize(t *testing.T) {
 		fmt.Println(err)
 	}
 	for i := 1; i <= 300; i++ {
-		file = SetCellStr(file, "SHEET3", fmt.Sprintf("c%d", i), randToken(5))
+		file = SetCellStr(file, "SHEET3", fmt.Sprintf("c%d", i), strconv.Itoa(i))
 	}
 	err = Save(file, "./test/Workbook_2.xlsx")
 
@@ -47,9 +37,3 @@ func TestExcelize(t *testing.T) {
 		fmt.Println(err)
 	}
 }
-
-func randToken(length int) string {
-	b := make([]byte, length)
-	rand.Read(b)
-	return fmt.Sprintf("%x", b)
-}