_:B487a91f873764b4f025434ed430e6f82 . "Horst W.J." . "Rittel" . "Horst W.J. Rittel" . . . . "Rittel, Horst W.J." . . _:B487a91f873764b4f025434ed430e6f82 . _:B487a91f873764b4f025434ed430e6f82 . _:B487a91f873764b4f025434ed430e6f82 "2023-05-21"^^ . _:B487a91f873764b4f025434ed430e6f82 . _:B487a91f873764b4f025434ed430e6f82 . _:B487a91f873764b4f025434ed430e6f82 "067781152" . _:B487a91f873764b4f025434ed430e6f82 . _:B487a91f873764b4f025434ed430e6f82 . _:B487a91f873764b4f025434ed430e6f82 .