Get DOIs to each Chapters of my book

I have written a book in Sinhala on “Doing Research and Publishing Results” to support upcoming researchers who are slower in reading and understanding English publications: texts, videos etc.

No International publisher would accept to publish my book as our Sinhala-speaking market is very small. Even Sri Lankan publishers are also not willing to publish it as the academic community is not adequate to make this project profitable.

Therefore, I have to publish it by myself, as a service to the Sri Lankan community, which cost me nearly LKR3.5 million (US$10,000.00). The benefits I expect are 1. The reputation/fame among Sri Lankan academics and 2. Citation to my book chapters (30 Chapters).

For this purpose, I need to assign DOIs for my book chapters.

Can you please guide me on how to achieve this in the most effective way (at least cost)?