“Báisàn Yúnhuā Wàijū Shǐshì” 白散雲花外居史士 is a composite pen name formed by telescoping two distinct pseudonyms: Báiyún Wàishǐ 白雲外史 (“Outer Historian of the White Clouds”) and Sànhuā Jūshì 散花居士 (“Flower-Scattering Layman”). These two writers collaborated on Hòu Hónglóumèng 後紅樓夢, a 30-chapter sequel to Hónglóu Mèng 紅樓夢, and published it with an elaborate apparatus falsely attributing it to Cáo Xuěqín 曹雪芹 as a genuine autograph sequel. Their real identities are unknown; no CBDB entry has been located for either pseudonymous author.
Kanripo works: KR4k0139 Hòu Hónglóumèng 後紅樓夢.