Q: Dear Expert: we wish to have a general instruction to publication of our own iBook.

There is some info for publishing in the iBookstore on this page :

http://www.apple.com/itunes/working-itunes/sell-content/books/book-faq.html

If you are using iBooks Author to produce the book and have specific questions about it then there are other forums on here :

creating ibooks : Creating Books for iBooks Store

iTunes connect : Sign-up / iTunes Connect