Li Shangyin and Du Mu are both called "Little Li Du".
1. Li Shangyin (about 813-about 858), whose courtesy name was Yishan, also named Yuxi (Xi) Sheng, and also Fan Nansheng, his ancestral home was Hanoi, Huaizhou (now Qinyang, Jiaozuo, Henan), and he was born in Xingyang, Zhengzhou (now Xingyang City, Zhengzhou, Henan Province), a famous poet in the late Tang Dynasty, and together with Du Mu, are known as "Little Li Du".
Li Shangyin was one of the few poets in the late Tang Dynasty and even the entire Tang Dynasty who deliberately pursued poetic beauty. He is good at poetry writing, and his parallel prose is also of high literary value. His poems are novel in conception and beautiful in style, especially some love poems and untitled poems, which are sentimental, beautiful and moving, and are widely read.
2. Du Mu (803-about 852), named Muzhi and Fanchuan Jushi, Han nationality, was born in Jingzhao Wannian (now Xi'an, Shaanxi). Du Mu was an outstanding poet and essayist in the Tang Dynasty.
Du Mu's poems are famous for their seven-character quatrains, and their content mainly focuses on chanting history and expressing feelings. His poems are handsome and full of historical things, and he achieved great success in the late Tang Dynasty. Du Mu was called "Xiao Du" to distinguish him from Du Fu, "Da Du". Together with Li Shangyin, he is called "Little Li Du".
Extended information:
There is also a pair of big Li Du in history, which is the collective name of Li Bai and Du Fu.
1. Li Bai (701-762), named Taibai, also known as Qinglian Jushi, also known as "Exiled Immortal", was hailed as "Poetry Immortal" by later generations, and was called "Li Bai" together with Du Fu. "Du", in order to distinguish them from the other two poets Li Shangyin and Du Mu, namely "Little Li Du", Du Fu and Li Bai are also collectively known as "Big Li Du".
2. Du Fu (712-770), named Zimei, who called himself Shaoling Yelao, was a great realist poet in the Tang Dynasty. Together with Li Bai, he was called "Li Du".