The phrase "worked in the library" is correct and usable in written English.
For example, you might say: "I worked in the library during my summer break."
From 1876 until 1882 Verner worked in the library of the University of Halle.
After the Revolution he worked in the library of the Soviet commissariat of education.
Mrs. Ramsey worked in the library and never lacked for boys needing help.
Mother brought in Ellis, an awkward boy of 20, who worked in the library, to give them advice.
She has chaperoned three field trips, worked in the library and helped set up a "mad scientist" dry ice center for a Halloween party.
"When I went to Queen's University, Belfast, I met people who had known him when he worked in the library there, so he felt like a local.
For centuries students of the Italian Renaissance have worked in the libraries of Florence which were the richest in this branch & the loss in this field is the greatest blow to the city.
What Heilbron's university contemporaries remember is that "she was always working in the library.
Today there are 1,400 public service people who work in the library's system.
The commentary is provided by a former Ph.D. student and an undergraduate who works in the library.
A young Chinese archeologist was working in the library, and I asked if he knew who had written the book.
