Wolf, Martin L., author
Philosophical Library, 1958
Buku Referensi
Roberts, Lawrence P., author
Weatherhill, 1976
Buku Referensi
Marcucci, Luisa, author
Studio Books , 1960
Buku Referensi
Watson Guptill Publications, 2002
Buku Teks
London: Tiger Books International, 1994,
Buku Referensi