An archive has opened in the German city of Göttingen dedicated to the late Nobel Prize winner Günter Grass. The author's publisher has said the collection will prove valuable for decades.
Ute Grass formally opened the archive of work by her late husband on Friday, some two months after his death, with the moment accompanied by the symbolic sounding of a tin drum.
The building houses a mass of material built up over the years during Grass' close association with his Göttingen-based publisher Gerhard Steidl. The writer left behind several containers including etchings, lithographs, drawings and texts.
The documents are to be made available for researchers and visitors from around the world and will be a valuable resource for decades to come, Steidl said.
An exhibit was also unveiled at the opening detailing the creative process behind Grass' final book, "Vonne Endlichkait" ("From Finiteness"), which is due to be published in August. It includes 65 drawings and numerous handwritten or typed manuscript pages.
'Frolicsome fables, forgotten faces'
The writer - well-known for his trademark handlebar moustache and pipe smoking - died on April 13, aged 87, from complications related to an infection.
Grass is known for having, over decades, pressed Germany to face up to its Nazi past. He won the 1999 Nobel Prize for Literature for his "frolicsome black fables portraying the forgotten face of history."
His body of work included "The Tin Drum," "Cat and Mouse," "Dog Days" and "From the Diary of a Snail."
There was an outcry in 2006 when Grass finally revealed that he had been called up into Hitler's notorious Waffen SS at the age of 17. The writer said he had remained silent for so long out of shame.
Further controversy came in 2012, when he ruffled feathers with a prose-poem "What Must Be Said," which portrayed Israel as the biggest threat to peace in the Middle East.