Pfeiffer, John
Time Incorporated, 1964
Buku Referensi
Pollard, Thomas D. (Thomas Dean), 1942-
Saunders Elsevier, 2008
Buku Teks
De Robertis, Eduardo D. P., 1913-
Saunders, 1968
Buku Teks
Pollard, Thomas D. (Thomas Dean), 1942-
Saunders Elsevier, 2008
Buku Teks
Karp, Gerald
John Wiley & Sons Inc, 2010
Buku Teks