1. Nguyen Trai and his Nôm poetry collection - Quoc am thi tap
Quoc am thi tap (國音詩集) is the 14 - 15th century collection of Nôm poetry written by (Nguyen Trai 1380- 1442) – the most famous poet of Vietnam. He was recognized as an international cultural celebrity by UNESCO in 1980. Nguyen Trai is counted as “the first man to construct Vietnamse Nôm literature” (prof. Đào Duy Anh). Quoc am thi tap is not only the development of literature, but also the progress of Nôm script, Vietnamse language and Vietnamese culture. The Nôm text Quoc am thi tap is a cultural inheritance, because there are 12,500 Nôm characters of 15th century in the text.
This poetic collection occupies an important place in the history of Vietnamese literature and culture. It is the most ancient Nôm poetry collection. And it's considered as the pre-eminent work of Vietnamese literature, and may be compared with The Tale of Kieu by Nguyen Du.
2. The introduction of “A Dictionary of 15th Century Ancient Vietnamese”