You will gain no benefit from any book unless you read it!

Similarly, you will gain most benefit from this forum if you Read the instructions - and follow them!
When you posted this question, you saw these instructions:


Here's just a few links found by a search for "C books:"

http://www.8052.com/forum/read.phtml?id=69074
http://www.8052.com/forum/read.phtml?id=69100
http://www.8052.com/forum/read.phtml?id=67387
http://www.8052.com/forum/read.phtml?id=66220

You should also have noticed that there is a line of buttons down the left-hand side, including Did you check that out?

Keil also has a bibliography ("books page"): http://www.keil.com/books/8051books.asp