diff --git a/calc.go b/calc.go
index a2efbdb..c1e0b44 100644
--- a/calc.go
+++ b/calc.go
@@ -101,14 +101,15 @@ const (
 
 // formulaArg is the argument of a formula or function.
 type formulaArg struct {
-	SheetName string
-	Number    float64
-	String    string
-	List      []formulaArg
-	Matrix    [][]formulaArg
-	Boolean   bool
-	Error     string
-	Type      ArgType
+	SheetName            string
+	Number               float64
+	String               string
+	List                 []formulaArg
+	Matrix               [][]formulaArg
+	Boolean              bool
+	Error                string
+	Type                 ArgType
+	cellRefs, cellRanges *list.List
 }
 
 // Value returns a string data type of the formula argument.
@@ -181,8 +182,8 @@ func (fa formulaArg) ToList() []formulaArg {
 
 // formulaFuncs is the type of the formula functions.
 type formulaFuncs struct {
-	f     *File
-	sheet string
+	f           *File
+	sheet, cell string
 }
 
 // tokenPriority defined basic arithmetic operator priority.
@@ -235,6 +236,8 @@ var tokenPriority = map[string]int{
 //    CEILING.PRECISE
 //    CHOOSE
 //    CLEAN
+//    CODE
+//    COLUMN
 //    COMBIN
 //    COMBINA
 //    CONCAT
@@ -261,6 +264,8 @@ var tokenPriority = map[string]int{
 //    FACT
 //    FACTDOUBLE
 //    FALSE
+//    FIND
+//    FINDB
 //    FISHER
 //    FISHERINV
 //    FLOOR
@@ -363,7 +368,7 @@ func (f *File) CalcCellValue(sheet, cell string) (result string, err error) {
 	if tokens == nil {
 		return
 	}
-	if token, err = f.evalInfixExp(sheet, tokens); err != nil {
+	if token, err = f.evalInfixExp(sheet, cell, tokens); err != nil {
 		return
 	}
 	result = token.TValue
@@ -446,7 +451,7 @@ func newEmptyFormulaArg() formulaArg {
 //
 // TODO: handle subtypes: Nothing, Text, Logical, Error, Concatenation, Intersection, Union
 //
-func (f *File) evalInfixExp(sheet string, tokens []efp.Token) (efp.Token, error) {
+func (f *File) evalInfixExp(sheet, cell string, tokens []efp.Token) (efp.Token, error) {
 	var err error
 	opdStack, optStack, opfStack, opfdStack, opftStack, argsStack := NewStack(), NewStack(), NewStack(), NewStack(), NewStack(), NewStack()
 	for i := 0; i < len(tokens); i++ {
@@ -537,7 +542,7 @@ func (f *File) evalInfixExp(sheet string, tokens []efp.Token) (efp.Token, error)
 			if token.TType == efp.TokenTypeOperand && token.TSubType == efp.TokenSubTypeText {
 				argsStack.Peek().(*list.List).PushBack(newStringFormulaArg(token.TValue))
 			}
-			if err = f.evalInfixExpFunc(sheet, token, nextToken, opfStack, opdStack, opftStack, opfdStack, argsStack); err != nil {
+			if err = f.evalInfixExpFunc(sheet, cell, token, nextToken, opfStack, opdStack, opftStack, opfdStack, argsStack); err != nil {
 				return efp.Token{}, err
 			}
 		}
@@ -556,7 +561,7 @@ func (f *File) evalInfixExp(sheet string, tokens []efp.Token) (efp.Token, error)
 }
 
 // evalInfixExpFunc evaluate formula function in the infix expression.
-func (f *File) evalInfixExpFunc(sheet string, token, nextToken efp.Token, opfStack, opdStack, opftStack, opfdStack, argsStack *Stack) error {
+func (f *File) evalInfixExpFunc(sheet, cell string, token, nextToken efp.Token, opfStack, opdStack, opftStack, opfdStack, argsStack *Stack) error {
 	if !isFunctionStopToken(token) {
 		return nil
 	}
@@ -575,7 +580,7 @@ func (f *File) evalInfixExpFunc(sheet string, token, nextToken efp.Token, opfSta
 		argsStack.Peek().(*list.List).PushBack(newStringFormulaArg(opfdStack.Pop().(efp.Token).TValue))
 	}
 	// call formula function to evaluate
-	arg := callFuncByName(&formulaFuncs{f: f, sheet: sheet}, strings.NewReplacer(
+	arg := callFuncByName(&formulaFuncs{f: f, sheet: sheet, cell: cell}, strings.NewReplacer(
 		"_xlfn", "", ".", "").Replace(opfStack.Peek().(efp.Token).TValue),
 		[]reflect.Value{reflect.ValueOf(argsStack.Peek().(*list.List))})
 	if arg.Type == ArgError && opfStack.Len() == 1 {
@@ -1007,6 +1012,7 @@ func prepareValueRef(cr cellRef, valueRange []int) {
 // This function will not ignore the empty cell. For example, A1:A2:A2:B3 will
 // be reference A1:B3.
 func (f *File) rangeResolver(cellRefs, cellRanges *list.List) (arg formulaArg, err error) {
+	arg.cellRefs, arg.cellRanges = cellRefs, cellRanges
 	// value range order: from row, to row, from column, to column
 	valueRange := []int{0, 0, 0, 0}
 	var sheet string
@@ -4581,6 +4587,23 @@ func (fn *formulaFuncs) CLEAN(argsList *list.List) formulaArg {
 	return newStringFormulaArg(b.String())
 }
 
+// CODE function converts the first character of a supplied text string into
+// the associated numeric character set code used by your computer. The
+// syntax of the function is:
+//
+//    CODE(text)
+//
+func (fn *formulaFuncs) CODE(argsList *list.List) formulaArg {
+	if argsList.Len() != 1 {
+		return newErrorFormulaArg(formulaErrorVALUE, "CODE requires 1 argument")
+	}
+	text := argsList.Front().Value.(formulaArg).Value()
+	if len(text) == 0 {
+		return newNumberFormulaArg(0)
+	}
+	return newNumberFormulaArg(float64(text[0]))
+}
+
 // CONCAT function joins together a series of supplied text strings into one
 // combined text string.
 //
@@ -4639,6 +4662,63 @@ func (fn *formulaFuncs) EXACT(argsList *list.List) formulaArg {
 	return newBoolFormulaArg(text1 == text2)
 }
 
+// FIND function returns the position of a specified character or sub-string
+// within a supplied text string. The function is case-sensitive. The syntax
+// of the function is:
+//
+//    FIND(find_text,within_text,[start_num])
+//
+func (fn *formulaFuncs) FIND(argsList *list.List) formulaArg {
+	return fn.find("FIND", argsList)
+}
+
+// FINDB counts each double-byte character as 2 when you have enabled the
+// editing of a language that supports DBCS and then set it as the default
+// language. Otherwise, FINDB counts each character as 1. The syntax of the
+// function is:
+//
+//    FINDB(find_text,within_text,[start_num])
+//
+func (fn *formulaFuncs) FINDB(argsList *list.List) formulaArg {
+	return fn.find("FINDB", argsList)
+}
+
+// find is an implementation of the formula function FIND and FINDB.
+func (fn *formulaFuncs) find(name string, argsList *list.List) formulaArg {
+	if argsList.Len() < 2 {
+		return newErrorFormulaArg(formulaErrorVALUE, fmt.Sprintf("%s requires at least 2 arguments", name))
+	}
+	if argsList.Len() > 3 {
+		return newErrorFormulaArg(formulaErrorVALUE, fmt.Sprintf("%s allows at most 3 arguments", name))
+	}
+	findText := argsList.Front().Value.(formulaArg).Value()
+	withinText := argsList.Front().Next().Value.(formulaArg).Value()
+	startNum, result := 1, 1
+	if argsList.Len() == 3 {
+		numArg := argsList.Back().Value.(formulaArg).ToNumber()
+		if numArg.Type != ArgNumber {
+			return numArg
+		}
+		if numArg.Number < 0 {
+			return newErrorFormulaArg(formulaErrorVALUE, formulaErrorVALUE)
+		}
+		startNum = int(numArg.Number)
+	}
+	if findText == "" {
+		return newNumberFormulaArg(float64(startNum))
+	}
+	for idx := range withinText {
+		if result < startNum {
+			result++
+		}
+		if strings.Index(withinText[idx:], findText) == 0 {
+			return newNumberFormulaArg(float64(result))
+		}
+		result++
+	}
+	return newErrorFormulaArg(formulaErrorVALUE, formulaErrorVALUE)
+}
+
 // LEFT function returns a specified number of characters from the start of a
 // supplied text string. The syntax of the function is:
 //
@@ -5031,6 +5111,28 @@ func compareFormulaArgMatrix(lhs, rhs formulaArg, caseSensitive, exactMatch bool
 	return criteriaEq
 }
 
+// COLUMN function returns the first column number within a supplied reference
+// or the number of the current column. The syntax of the function is:
+//
+//    COLUMN([reference])
+//
+func (fn *formulaFuncs) COLUMN(argsList *list.List) formulaArg {
+	if argsList.Len() > 1 {
+		return newErrorFormulaArg(formulaErrorVALUE, "COLUMN requires at most 1 argument")
+	}
+	if argsList.Len() == 1 {
+		if argsList.Front().Value.(formulaArg).cellRanges != nil && argsList.Front().Value.(formulaArg).cellRanges.Len() > 0 {
+			return newNumberFormulaArg(float64(argsList.Front().Value.(formulaArg).cellRanges.Front().Value.(cellRange).From.Col))
+		}
+		if argsList.Front().Value.(formulaArg).cellRefs != nil && argsList.Front().Value.(formulaArg).cellRefs.Len() > 0 {
+			return newNumberFormulaArg(float64(argsList.Front().Value.(formulaArg).cellRefs.Front().Value.(cellRef).Col))
+		}
+		return newErrorFormulaArg(formulaErrorVALUE, "invalid reference")
+	}
+	col, _, _ := CellNameToCoordinates(fn.cell)
+	return newNumberFormulaArg(float64(col))
+}
+
 // HLOOKUP function 'looks up' a given value in the top row of a data array
 // (or table), and returns the corresponding value from another row of the
 // array. The syntax of the function is:
diff --git a/calc_test.go b/calc_test.go
index 1b04df8..8a07eef 100644
--- a/calc_test.go
+++ b/calc_test.go
@@ -715,6 +715,12 @@ func TestCalcCellValue(t *testing.T) {
 		// CLEAN
 		"=CLEAN(\"\u0009clean text\")": "clean text",
 		"=CLEAN(0)":                    "0",
+		// CODE
+		"=CODE(\"Alpha\")": "65",
+		"=CODE(\"alpha\")": "97",
+		"=CODE(\"?\")":     "63",
+		"=CODE(\"3\")":     "51",
+		"=CODE(\"\")":      "0",
 		// CONCAT
 		"=CONCAT(TRUE(),1,FALSE(),\"0\",INT(2))": "TRUE1FALSE02",
 		// CONCATENATE
@@ -723,6 +729,20 @@ func TestCalcCellValue(t *testing.T) {
 		"=EXACT(1,\"1\")":     "TRUE",
 		"=EXACT(1,1)":         "TRUE",
 		"=EXACT(\"A\",\"a\")": "FALSE",
+		// FIND
+		"=FIND(\"T\",\"Original Text\")":   "10",
+		"=FIND(\"t\",\"Original Text\")":   "13",
+		"=FIND(\"i\",\"Original Text\")":   "3",
+		"=FIND(\"i\",\"Original Text\",4)": "5",
+		"=FIND(\"\",\"Original Text\")":    "1",
+		"=FIND(\"\",\"Original Text\",2)":  "2",
+		// FINDB
+		"=FINDB(\"T\",\"Original Text\")":   "10",
+		"=FINDB(\"t\",\"Original Text\")":   "13",
+		"=FINDB(\"i\",\"Original Text\")":   "3",
+		"=FINDB(\"i\",\"Original Text\",4)": "5",
+		"=FINDB(\"\",\"Original Text\")":    "1",
+		"=FINDB(\"\",\"Original Text\",2)":  "2",
 		// LEFT
 		"=LEFT(\"Original Text\")":    "O",
 		"=LEFT(\"Original Text\",4)":  "Orig",
@@ -786,6 +806,12 @@ func TestCalcCellValue(t *testing.T) {
 		"=CHOOSE(4,\"red\",\"blue\",\"green\",\"brown\")": "brown",
 		"=CHOOSE(1,\"red\",\"blue\",\"green\",\"brown\")": "red",
 		"=SUM(CHOOSE(A2,A1,B1:B2,A1:A3,A1:A4))":           "9",
+		// COLUMN
+		"=COLUMN()":                "3",
+		"=COLUMN(Sheet1!A1)":       "1",
+		"=COLUMN(Sheet1!A1:B1:C1)": "1",
+		"=COLUMN(Sheet1!F1:G1)":    "6",
+		"=COLUMN(H1)":              "8",
 		// HLOOKUP
 		"=HLOOKUP(D2,D2:D8,1,FALSE)":          "Jan",
 		"=HLOOKUP(F3,F3:F8,3,FALSE)":          "34440",
@@ -1325,6 +1351,9 @@ func TestCalcCellValue(t *testing.T) {
 		// CLEAN
 		"=CLEAN()":    "CLEAN requires 1 argument",
 		"=CLEAN(1,2)": "CLEAN requires 1 argument",
+		// CODE
+		"=CODE()":    "CODE requires 1 argument",
+		"=CODE(1,2)": "CODE requires 1 argument",
 		// CONCAT
 		"=CONCAT(MUNIT(2))": "CONCAT requires arguments to be strings",
 		// CONCATENATE
@@ -1332,6 +1361,18 @@ func TestCalcCellValue(t *testing.T) {
 		// EXACT
 		"=EXACT()":      "EXACT requires 2 arguments",
 		"=EXACT(1,2,3)": "EXACT requires 2 arguments",
+		// FIND
+		"=FIND()":                 "FIND requires at least 2 arguments",
+		"=FIND(1,2,3,4)":          "FIND allows at most 3 arguments",
+		"=FIND(\"x\",\"\")":       "#VALUE!",
+		"=FIND(\"x\",\"x\",-1)":   "#VALUE!",
+		"=FIND(\"x\",\"x\",\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",
+		// FINDB
+		"=FINDB()":                 "FINDB requires at least 2 arguments",
+		"=FINDB(1,2,3,4)":          "FINDB allows at most 3 arguments",
+		"=FINDB(\"x\",\"\")":       "#VALUE!",
+		"=FINDB(\"x\",\"x\",-1)":   "#VALUE!",
+		"=FINDB(\"x\",\"x\",\"\")": "strconv.ParseFloat: parsing \"\": invalid syntax",
 		// LEFT
 		"=LEFT()":          "LEFT requires at least 1 argument",
 		"=LEFT(\"\",2,3)":  "LEFT allows at most 2 arguments",
@@ -1383,6 +1424,11 @@ func TestCalcCellValue(t *testing.T) {
 		"=CHOOSE()":                "CHOOSE requires 2 arguments",
 		"=CHOOSE(\"index_num\",0)": "CHOOSE requires first argument of type number",
 		"=CHOOSE(2,0)":             "index_num should be <= to the number of values",
+		// COLUMN
+		"=COLUMN(1,2)":          "COLUMN requires at most 1 argument",
+		"=COLUMN(\"\")":         "invalid reference",
+		"=COLUMN(Sheet1)":       "invalid column name \"Sheet1\"",
+		"=COLUMN(Sheet1!A1!B1)": "invalid column name \"Sheet1\"",
 		// HLOOKUP
 		"=HLOOKUP()":                     "HLOOKUP requires at least 3 arguments",
 		"=HLOOKUP(D2,D1,1,FALSE)":        "HLOOKUP requires second argument of table array",
diff --git a/cell.go b/cell.go
index 892a906..912ee6a 100644
--- a/cell.go
+++ b/cell.go
@@ -519,11 +519,14 @@ func (f *File) GetCellRichText(sheet, cell string) (runs []RichTextRun, err erro
 			Text: v.T.Val,
 		}
 		if nil != v.RPr {
-			font := Font{}
+			font := Font{Underline: "none"}
 			font.Bold = v.RPr.B != nil
 			font.Italic = v.RPr.I != nil
-			if v.RPr.U != nil && v.RPr.U.Val != nil {
-				font.Underline = *v.RPr.U.Val
+			if v.RPr.U != nil {
+				font.Underline = "single"
+				if v.RPr.U.Val != nil {
+					font.Underline = *v.RPr.U.Val
+				}
 			}
 			if v.RPr.RFont != nil && v.RPr.RFont.Val != nil {
 				font.Family = *v.RPr.RFont.Val