_:Bd54dc653139a7ff2bec79e3c0f4f550d . "Richard A." . "Hellman" . "Richard A. Hellman" . . . . "Hellman, Richard A." . . _:Bd54dc653139a7ff2bec79e3c0f4f550d . _:Bd54dc653139a7ff2bec79e3c0f4f550d . _:Bd54dc653139a7ff2bec79e3c0f4f550d "2023-05-20"^^ . _:Bd54dc653139a7ff2bec79e3c0f4f550d . _:Bd54dc653139a7ff2bec79e3c0f4f550d . _:Bd54dc653139a7ff2bec79e3c0f4f550d "149243693" . _:Bd54dc653139a7ff2bec79e3c0f4f550d . _:Bd54dc653139a7ff2bec79e3c0f4f550d . _:Bd54dc653139a7ff2bec79e3c0f4f550d .