diff --git a/.travis.yml b/.travis.yml
index 88968815a10342ff598d3f6bd3327e3ce150ae46..d9f3ffd2fd529497bf42deee94bdfcfcab7f4410 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 0935d4798cddc49448d21c9ca60ef405f6817b31..0bd7c02874ea128f768157ae25cb02304e784f05 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 c2848a057a6582bbe244df950068ff8757c796eb..b392264b4c65c350ea7809b8ad1fe371e29dfca0 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)
-}