I am immediately discouraged by a statement on the cover; that the leading UNIX shells are C, Bourne and Korn. This is a highly dubious claim. Inside the cover there is no mention of Bash (default shell on the free BSD UNIX), nor of tcsh.
Try as I might I cannot find any instructions in the text or on the media on how to mount the CDROM or extract the contained code. Given the various UNIX flavours out there and the resulting variation in mount commands, this is no small oversight, especially for a book aimed at beginners. After a good guess, I was able to mount OK, but then I'm long in the tooth!
Some of the sources were submitted in 1994 and in a comment the author admits that he will be 'out of the country' for some time and perhaps available only by snail mail! Good luck.
Another oversight is the absence of any index entry on the characters: ?,$,),(,=,# - there are so many. These play an essential part in shell syntax and it is important to be able to reference their use quickly. Scanning other people's, often uncommented, code and deciphering it is an essential part of the learning process. In the early days one needs a good index to hand.
On the positive side the examples are profuse and easy to understand. Each shell is dealt with in terms of its command line interactive use (prompts, history, redirection, pipes) and then in terms of script programming.
Importantly, on the positive side one has three shells and powerful UNIX utilities like awk, grep and sed all under the one tome. Each of these is covered, some separately, in other books. So the decision to buy this book can be based on simple economics; both of shelf space and of pocket. It is better to have one at this price rather than 4 or 5 at£25 each. However, I am dubious as the Bourne and Korn shells are not sufficiently different to warrant the expense. Most everyday users will adopt one shell and stick to it.