I just received this question via email:
Q "... in your book, all the exercises are written for 4-strings bass in standard tuning (as far as I know). I´m just a beginner at bass and I have a 5-string bass (eadgc). Is it easy to adapt the exercises in your book to take advantage of the extra string? "
A. It is very easy to just add another string to the mix. The primary harmonics are going to be CEGBb for a C string. You'll find that all the locations for harmonics remain in the same location for each given string no matter what the tuning. By the way, I do use several alternate tunings in my book, "Bass Harmonics: New Concepts and Techniques".
Using harmonics still remains a new subject. So even though you're at the beginning of your playing career, you'll find this is the best time to start. The use of harmonics will simply become integrated into your own style. I'm impressed that you are studying harmonics so early, and wish you all the best!