This new, revised impression of the original 2007 edition of Omar Khayyām: poet – rebel – astronomer  is now on sale in the UK from https://www.amazon.co.uk/Hazhir- Teimourian/e/B00J9ODFLY/ref=sr_tc_2_0?qid=1423652706&sr=1-2- ent%20   in both print and e-book formats. In the United States and elsewhere, please go to your local Amazon site and search for Omar Khayyam: Poet, Rebel, Astronomer.