A paper accepted by BCCA 2023 July 25 , 2023 July 25, 2023Taeho Boyang Li, Bingyu Shen, Qing Lu, Taeho Jung, Yiyu Shi “Proof-of-Federated-Learning-Subchain: Free Partner Selection Subchain Based on Federated Learning” The Fifth International Conference on Blockchain Computing and Applications (BCCA 2023)