diff --git a/doc/progs/interface2.go b/doc/progs/interface2.go
index e2716cf..2deba32 100644
--- a/doc/progs/interface2.go
+++ b/doc/progs/interface2.go
@@ -1,3 +1,9 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This file contains the code snippets included in "The Laws of Reflection."
+
 package main
 
 import (
@@ -39,11 +45,14 @@
 	type MyInt int
 	var x MyInt = 7
 	v := reflect.ValueOf(x)
+	// STOP OMIT
 	// START f3b OMIT
 	y := v.Interface().(float64) // y will have type float64.
 	fmt.Println(y)
+	// STOP OMIT
 	// START f3c OMIT
 	fmt.Println(v.Interface())
+	// STOP OMIT
 	// START f3d OMIT
 	fmt.Printf("value is %7.1e\n", v.Interface())
 	// STOP OMIT
@@ -69,6 +78,7 @@
 	// START f6 OMIT
 	var x float64 = 3.4
 	v := reflect.ValueOf(x)
+	// STOP OMIT
 	// START f6b OMIT
 	v.SetFloat(7.1)
 	// STOP OMIT
@@ -80,9 +90,11 @@
 	p := reflect.ValueOf(&x) // Note: take the address of x.
 	fmt.Println("type of p:", p.Type())
 	fmt.Println("settability of p:", p.CanSet())
+	// STOP OMIT
 	// START f7b OMIT
 	v := p.Elem()
 	fmt.Println("settability of v:", v.CanSet())
+	// STOP OMIT
 	// START f7c OMIT
 	v.SetFloat(7.1)
 	fmt.Println(v.Interface())
@@ -104,6 +116,7 @@
 		fmt.Printf("%d: %s %s = %v\n", i,
 			typeOfT.Field(i).Name, f.Type(), f.Interface())
 	}
+	// STOP OMIT
 	// START f8b OMIT
 	s.Field(0).SetInt(77)
 	s.Field(1).SetString("Sunset Strip")