The cooperative distribution between private publishing companies and publishing houses is usually dominated by private companies, and the publishing houses are in a passive cooperative position. Because at this time, the publishing resources are in the hands of private publishing companies, but they don't have ISBN, so they must cooperate with publishing houses to publish (publishing houses have ISBN resources). For an inappropriate example, this way of cooperation is similar to "giving birth to children by sperm", and this "essence" is ISBN. The answer upstairs is correct. Let me add something. The main channel is Xinhua Bookstore. The second channel is private book channel, such as private book wholesale and retail companies in book wholesale markets around the country. As state-owned enterprises, Xinhua Bookstore and Publishing House are more mutually recognized within the system. Generally, Xinhua Bookstore system prefers to purchase goods from publishing houses. If a book of a private company wants to enter Xinhua Bookstore, it generally needs the relevant authorization certificate.

Is that clear?