The Ryo implements Cryptonight-GPU ASIC Resistant algorithm. Ryo, as a fork from Monero which itself was initially based on the CryptoNote protocol, inherits all whitepapers and academic studies from CryptoNote and Monero Research Lab. The fallout from Sumokoin's premine SNAFU and their rash decision to hard fork back to ASIC friendly Cryptonight algorithm resulted in a community backed effort to maintain the original intent of the project of improved privacy and to stay true to GPU miners with CN-Heavy. At block height 137500 what is currently SUMO/RYO have transitioned into RYO and SUMO. Now they are running on a separate chains.