"Esaclorobutadiene"@it . "Esaclorobutadiene — Codice CAS: 87-68-3"@it . . . "Hexachlorobuta-1,3-diene"@en . "CAS:87-68-3" . "Hexachlorobuta-1,3-diene — CAS Identifier: 87-68-3"@en . . . .