[1] In 1967 she was employed as a special researcher at the Bibliothèque nationale de France, where she discovered in 1972 the second volume of JikjiSimcheYojeol, the world's oldest extant book, printed with movable metal type, while sorting out Korean-related materials at the library.

In 1900 the existence of JikjiSimcheYojeol was firstly introduced to the world by Victor Collin de Plancy, but it was not widely showed.

[5][6] In 1975 she discovered the Owegujanggak, a collection of royal protocols of the Joseon dynasty, which had been seized as part of a punitive expedition by the French against Korea in 1866.

[7] Park publicly advocated for their return to the Republic of Korea,[8][9] which resulted in 75 volumes of the Owegujanggak being returned on a renewable lease in April 2011, following an agreement in March between the national museums of France and the Republic of Korea.

[10] She retired from the Bibliothèque nationale de France in 1982 but continued to research and advocate for the return of these documents.