by Johannes Hochtl ...[and others]
Verlag Enzyklopadie Leipzig, 1960
Buku Referensi
Tiger Books International, 1994
Buku Referensi
Methuen & Co. ; Langenscheidt Kg., 1962
Buku Referensi
Methuen & Co. ; Langenscheidt Kg., 1963
Buku Referensi
New York, 1978
Buku Referensi