"Ecology." . . "Geografía Discursos, ensayos, conferencias." . . "Unió Soviètica." . . "Geography and ecology : a collection of articles, 1971-1981 : (Transl. from the Russian)" . "Geography and ecology : a collection of articles 1971-1981" . . "Geografiâ i èkologiâ" . . . . "Geography and ecology : A collection of articles 1971-1981" . . . . . "Geography and ecology : a collection of articles : 1971-1981" . . . . . . . . . . . . . . . . . . . . . . . . "Geography and ecology : a collection of articles, 1971-1981" . "Geography and ecology : a collection of articles, 1971-1981"@en . . . "Geografija i ėkologija" . . "Biogeography." . . "Protecció de la natura." . . "Biogéographie." . . "Écologie humaine." . . "Écologie." . . "Geografia." . . . . "Géographie humaine." . . "Géographie sociale." . . "Ecologia." . . "Ecología Discursos, ensayos, conferencias." . . "Recursos naturals." . .