It all began in Berlin. Long prior to the launch of Ethereum, the earliest builders and co-founders gathered in Kreuzberg in late November of 2014 to outline their work and designs for the future of Ethereum at a meetup called "ÐΞVcon-0".
How to Sell Ideas
By Vinay Gupta
Solidity, Vision and Roadmap
By Gavin Wood, Christian Reitwiessner
Ethereum 1.x: On blockchain interop and scaling
By Vlad Zamfir, Vitalik Buterin