I am happy to say that one of my research orineted book is published today by Amazon KDP,USA. I did this research for more than one and half years. Message from Amazon KDP Hello, Congratulations, your book “Optimization of Bohr's Theory of Hydrogen atom” is now live and available for purchase in the Kindle Store and enrolled in KDP Select! If you republished your book, your changes will be published based on these timelines. We hope you enjoy the benefits of KDP Select. In addition to your KDP royalties, you’ll earn a share of the monthly global fund from Kindle Unlimited for each page a customer reads in your book for the first time. Plus, you can use the book promotion tools, including Kindle Countdown Deals, time-bound promotional discounting on Amazon.com or Amazon.co.uk, or a Free Book Promotion.