The phrase "a key document in" is correct and usable in written English.
It can be used to emphasize the importance of a specific document within a particular context or field.
Example: "The report serves as a key document in our ongoing research on climate change."
Alternatives: "an essential document in" or "a crucial document in".
The second record remains a key document in the history of street rap, honoring Jay-Z's upbringing in the Marcy projects.
Perhaps the most significant is the Defense against the Detractors of Florence, a key document in the development of modern republicanism.
Saving the Media will be a key document in a debate whose stakes are nothing less crucial than the vitality of democracy.
Benjamin Jones (NYT) PHILIPPINES: CONFLICTING TESTIMONY President Joseph Estrada and his chief accuser made directly contradictory statements about a $100,000 check that is a key document in Mr. Estrada's impeachment trial.
It was a key document in the development of punk as well as an album that neatly bookends the two decades of rock'n'roll that began with Elvis in 1956.
A key document in the Eastern theory is the inscription on a stone grave stela found on the island of Lemnos near the coast of Anatolia that shows remarkable lexical and structural similarities with the Etruscan language.
The summit was announced as Macedonia came a step closer to becoming the alliance's 30th member when allies signed a key document at a ceremony in Brussels.
For another, Pope Francis talks a strong view of the special calling and sanctity of the priesthood, so he is unlikely to approve mixing that vocation with other roles.More significantly, Pope Francis has himself been responsible for developing a refined version of liberation theology, as the author of a key document issued at a bishops' conference in Aparecida, Brazil in 2007.
"UNICEF's global mission is to ensure and promote the rights of children and women, a mission that is guided by the Convention on the Rights of the Child, a key document that we will look at in detail," said Mahboob Shareef, UNICEF representative in Turkmenistan, when opening the seminar on Tuesday.
Tate has issued this key document in a nice new edition.
It is the key document in a crackdown that pits free-spirited yogis against lumbering state governments, which, unlike those they are trying to regulate, are not always known for their flexibility.
