"0"^^ . . "105688169"^^ . . "trouble that cannot be overcome by a single effort because of its many aspects or its persistent and pervasive quality; \"we may be facing a hydra that defies any easy solution\""@en-us . "105359390"@en-us . . "05688169-n"^^ . . "hydra"@en-us . . "hydra"^^ . . . . . "0.75"^^ . .