Publishers and Authors are pretty Old School
They are not very tech savvy
Here are some things to keep in mind, as you talk Authors and Publishers into embracing your exciting new technology

1) You have to make it zero tech for them. They should be able to use it without having to know even an iota of technology

2) You have to conduct business in a traditional style. Common courtesy. Things moving a bit slow. Everyone very polite to each other
Despite this, you have to move as fast as possible

3) Publishers trust other Publishers. Authors trust other Authors
Leverage that. Show them who your customers are. Show them Testimonials

4) Publishers won't understand what you are selling them until and unless you talk in their language
They won't understand even then. They will, however, be open to participating

5) Authors won't understand what you are selling them until you talk in terms of what pain point you are eliminating for them
Authors have completely different motivations from normal end customers

6) You have to keep moving as fast as you can, while understanding the ecosystem and adjusting your sales and marketing for this unique and peculiar market

7) Pick and choose who you work with very very carefully

8) Do not let any large established company in the ecosystem buy equity or a controlling stake
Their first move would be to just buy you/partner with you, and kill you off. They fear what they cannot understand

9) Look at the companies behind the companies. It's a $100 billion a year market (in the US alone) when you combine print books with textbooks and medical and legal journals. There is a set of 10 to 14 companies that control everything
Those are the companies you would have to work with, sooner or later

10) Tech companies like Google and Amazon would just try to kill you if they think your product is good. They have no desire to do anything good for the ecosystem
They will especially come after you if you give Authors or Publishers any sort of Control over their Destiny

11) Be very careful who you take funding from
There have been a few cases where companies with great ambition took funding from the wrong people. Then the founders/leaders were kicked out. The company became just a run of the mill pointless company

12) Don't understimate how dangerous the large tech companies and the large Publishers are
Google controls Search and the Android Play App Store
Amazon controls the ebook store and the counting
Publishers have control of most of the best authors
You better have some way to nullify most of these weapons

13) Never ever ever focus on the low end of the market

14) Do not expect rational behavior. As the market is changing very fast, everyone is on edge
Publishers don't want to lose their crown
Large tech companies don't want to lose their dream of becoming the new Kings
Authors don't want to lose their livelihood
EVERYONE is scared of having to change and adapt
They will all react in irrational ways if your product promises change
On the other hand, if you can show them how they can avoid change, they will do anything for you

15) You will have to drag your customers, often kicking and screaming, into the Future

It's not an easy ecosystem at all. The one silver lining is that everyone is so scared of technology and change, that an actual transformational technology could/would/should easily sweep through and take over the entire ecosystem

It's almost as if everyone in the ecosystem is waiting for someone to come in and show them the path forward

Perhaps it can be You!