文選
As tutor to the Emperors Montoku and Seiwa, Koreyoshi lectured on the Wen Xuan and the Book of Han, and the imperial edicts and prayers he drew up as chief draftsman still remain today. With Miyako no Yoshika and others he compiled the "Nihon Montoku Tennō Jitsuroku". He also participated in the compilation of the , an amendment to the Ritsuryō legal system. Personally, he wrote texts including the , , , and . A collection of his poetry was called the .