I want to make my table of contents to have the words "Chapter", "Title" and "Page" written in uppercase, like "CHAPTER", "TITLE" and "PAGE". My document class is Book. How can I do it?

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Please provide additional information (e.g. the document class). A minimal working example would be even better. –  lockstep May 14 '11 at 9:52
Solution found, I simply edited the style file of my document class! Not a very good idea, but it worked :D –  Sérgio May 16 '11 at 4:02
Rather than editing the question title as "[SOLVED]", you should write a separate (self-)answer. –  lockstep May 16 '11 at 5:21
A better option might be to use the titlesec package as described in this question about the table of contents –  Peter Grill Jul 18 '11 at 0:51

If you would like to change certain commonly used names, check if they are stored in a macro. There are common macros such as \chaptername, \partname, etc. You could redefine it, which would allow consistent use through the complete document, such as

\renewcommand*{\chaptername}{CHAPTER}


If you use the babel package, which is very recommendable, you should do it a bit differently, using the \addto command, otherwise babel would override your definition. Here's a complete example for you:

\documentclass{book}
\usepackage[english]{babel}

In your comment you said that you changed the style file. I would never do that since it would have effect on each other file which uses that class or style, respectively. Instead, I would use \renewcommand or \renewenvironment in the document preamble, copying the original definition there and making my changes - just in my own preamble, leaving the class/style untouched.