《资治通鉴·唐纪·唐纪七十五》
柳曾任御史大夫，皇帝想委任他做宰相，宦官们憎恶他，因而长期贬职在外。
玼御史大夫，上欲以为相。宦官恶之，故久谪于外。
Liu served as the imperial minister. The emperor wanted to appoint him as prime minister, but eunuchs hated him, so he was demoted for a long time.