"1850Z"^^ . . "Roberto Ivens (Ponta Delgada, June 12, 1850, - January 28, 1898, Dafundo, Oeiras) was a Portuguese explorer of Africa, geographer, colonial administrator, and an officer of the Portuguese Navy."@en . "1850-06-12Z"^^ . . . . . "1898Z"^^ . . "Roberto Ivens"@en . . . . . "1898-01-28Z"^^ . .