Peter Barth and Herbert Remmert have done it again. For the second time in a little more than a year, we learn they’ve discovered previously unknown works by a German expressionist.

Last year the owners of Remmert Gallery in Dusseldorf discovered a prepatory watercolor for “Germany, a Winter’s Fairytale” by George Grosz. It was a remarkable find since the original has been missing since 1933. It was presumeably destroyed by the Nazis who felt threatened by its content.

This year, Barth and Remmert uncovered four works by Otto Dix. They were discovered on the Bavarian estate of Hans and Martha Koch. The trove includes three water colors and a prepatory drawing of the art dealer Alfred Flechtheim.

Hans Koch was a kidney and bladder specialist from Dusseldorf. He was a noted art collector whose portrait Dix painted in 1921. His wife Martha also posed for the artist then left Hans for him. She would become Mrs. Otto Dix. The Doctor was undisturbed by this event since he was already romantically involved with his wife’s sister. The Dixes and the Kochs would remain friends.

Gallery Remmert plans to show the newly discovered pieces along with other works in an exhibition in Düsseldorf to mark Dix’s 120th birthday later this year.

Read more: [Otto Dix: Online Catalog]