The Library of Congress is acquiring what’s arguably a theater gold mine: the manuscripts and papers of Neil Simon, the most commercially successful American playwright of the 20th century.

The man behind works such as Come Blow Your Horn, Barefoot in the Park, Biloxi Blues, and The Odd Couple, Simon, who died in 2018, received more combined Oscar and Tony Award nominations than any other writer. He also earned a Pulitzer Prize for his play Lost in Yonkers and is the only playwright to have four Broadway plays running simultaneously.

“Neil Simon’s work has left an undeniable mark on American culture and theater,” said Librarian of Congress Carla Hayden in a press release. “The donation of Simon’s papers to our nation’s library is a treasured addition to our holdings that enhances our performing arts collection as one of the best in the world. It also ensures Simon’s legacy is preserved for generations to come.”

Donated by way of Simon’s widow, the actress Elaine Joyce Simon, the collection includes approximately 7,700 items that provide an intimate peek into Simon’s creative process and life. Materials include scripts, notes, outlines, handwritten first drafts, and typescripts, helping piece together the evolution of Simon’s shows. Also in the collection are several shows that were never completed or produced, one of which, The Merry Widows, was written for Bette Midler and Whoopi Goldberg.

To celebrate the acquisition, Sex and the City star Sarah Jessica Parker and her husband, actor Matthew Broderick, the titular teenager in Ferris Bueller’s Day Off, will be at the library tonight. The two are starring in the Broadway revival of Simon’s play, Plaza Suite, directed by John Benjamin Hickey, who will moderate a conversation with the two actors. Earlier in his career, Broderick performed in several of Simon’s plays, winning a Tony Award for his role in Brighton Beach Memoirs.